Sample records for joint total joint

  1. 21 CFR 872.3940 - Total temporomandibular joint prosthesis.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Total temporomandibular joint prosthesis. 872.3940... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3940 Total temporomandibular joint prosthesis. (a) Identification. A total temporomandibular joint prosthesis is a device that is intended to be...

  2. 21 CFR 872.3940 - Total temporomandibular joint prosthesis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Total temporomandibular joint prosthesis. 872.3940... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3940 Total temporomandibular joint prosthesis. (a) Identification. A total temporomandibular joint prosthesis is a device that is intended to be...

  3. Medicare Reimbursement for Total Joint Arthroplasty: The Driving Forces.

    PubMed

    Padegimas, Eric M; Verma, Kushagra; Zmistowski, Benjamin; Rothman, Richard H; Purtill, James J; Howley, Michael

    2016-06-15

    Total joint arthroplasty is a large and growing part of the U.S. Medicare budget, drawing attention to how much providers are paid for their services. The purpose of this study was to examine the variables that affect total joint arthroplasty reimbursement. Along with standard economic variables, we include unique health-care variables. Given the focus on value in the Affordable Care Act, the model examines the relationship of the quality of care to total joint arthroplasty reimbursement. We hoped to find that reimbursement patterns reward quality and reflect standard economic principles. Multivariable regression was performed to identify variables that correlate with Medicare reimbursement for total joint arthroplasty. Inpatient charge or reimbursement data on Medicare reimbursements were available for 2,750 hospitals with at least 10 discharges for uncomplicated total joint arthroplasty from the Centers for Medicare & Medicaid Services (CMS) for fiscal year 2011. Reimbursement variability was examined by using the Dartmouth Atlas to group institutions into hospital referral regions and hospital service areas. Independent variables were taken from the Dartmouth Atlas, CMS, the WWAMI (Washington, Wyoming, Alaska, Montana, Idaho) Rural Health Research Center, and the United States Census. There were 427,207 total joint arthroplasties identified, with a weighted mean reimbursement of $14,324.84 (range, $9,103 to $38,686). Nationally, the coefficient of variation for reimbursements was 0.19. The regression model accounted for 52.5% of reimbursement variation among providers. The total joint arthroplasty provider volume (p < 0.001) and patient satisfaction (p < 0.001) were negatively correlated with reimbursement. Government ownership of a hospital (p < 0.001) and higher Medicare costs (p < 0.001) correlated positively with reimbursement. Medicare reimbursements for total joint arthroplasty are highly variable. Greater reimbursement was associated with lower patient

  4. 21 CFR 872.3940 - Total temporomandibular joint prosthesis.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Total temporomandibular joint prosthesis. 872.3940 Section 872.3940 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3940 Total temporomandibular joint...

  5. Alloplastic total temporomandibular joint replacements: do they perform like natural joints? Prospective cohort study with a historical control.

    PubMed

    Wojczyńska, A; Leiggener, C S; Bredell, M; Ettlin, D A; Erni, S; Gallo, L M; Colombo, V

    2016-10-01

    The aim of this study was to qualitatively and quantitatively describe the biomechanics of existing total alloplastic reconstructions of temporomandibular joints (TMJ). Fifteen patients with unilateral or bilateral TMJ total joint replacements and 15 healthy controls were evaluated via dynamic stereometry technology. This non-invasive method combines three-dimensional imaging of the subject's anatomy with jaw tracking. It provides an insight into the patient's jaw joint movements in real time and provides a quantitative evaluation. The patients were also evaluated clinically for jaw opening, protrusive and laterotrusive movements, pain, interference with eating, and satisfaction with the joint replacements. The qualitative assessment revealed that condyles of bilateral total joint replacements displayed similar basic motion patterns to those of unilateral prostheses. Quantitatively, mandibular movements of artificial joints during opening, protrusion, and laterotrusion were all significantly shorter than those of controls. A significantly restricted mandibular range of motion in replaced joints was also observed clinically. Fifty-three percent of patients suffered from chronic pain at rest and 67% reported reduced chewing function. Nonetheless, patients declared a high level of satisfaction with the replacement. This study shows that in order to gain a comprehensive understanding of complex therapeutic measures, a multidisciplinary approach is needed. Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  6. Subsequent Total Joint Arthroplasty After Primary Total Knee or Hip Arthroplasty

    PubMed Central

    Sanders, Thomas L.; Maradit Kremers, Hilal; Schleck, Cathy D.; Larson, Dirk R.; Berry, Daniel J.

    2017-01-01

    Background: Despite the large increase in total hip arthroplasties and total knee arthroplasties, the incidence and prevalence of additional contralateral or ipsilateral joint arthroplasty are poorly understood. The purpose of this study was to determine the rate of additional joint arthroplasty after a primary total hip arthroplasty or total knee arthroplasty. Methods: This historical cohort study identified population-based cohorts of patients who underwent primary total hip arthroplasty (n = 1,933) or total knee arthroplasty (n = 2,139) between 1969 and 2008. Patients underwent passive follow-up through their medical records beginning with the primary total hip arthroplasty or total knee arthroplasty. We assessed the likelihood of undergoing a subsequent total joint arthroplasty, including simultaneous and staged bilateral procedures. Age, sex, and calendar year were evaluated as potential predictors of subsequent arthroplasty. Results: During a mean follow-up of 12 years after an initial total hip arthroplasty, we observed 422 contralateral total hip arthroplasties (29% at 20 years), 76 contralateral total knee arthroplasties (6% at 10 years), and 32 ipsilateral total knee arthroplasties (2% at 20 years). Younger age was a significant predictor of contralateral total hip arthroplasty (p < 0.0001), but not a predictor of the subsequent risk of total knee arthroplasty. During a mean follow-up of 11 years after an initial total knee arthroplasty, we observed 809 contralateral total knee arthroplasties (45% at 20 years), 31 contralateral total hip arthroplasties (3% at 20 years), and 29 ipsilateral total hip arthroplasties (2% at 20 years). Older age was a significant predictor of ipsilateral or contralateral total hip arthroplasty (p < 0.001). Conclusions: Patients undergoing total hip arthroplasty or total knee arthroplasty can be informed of a 30% to 45% chance of a surgical procedure in a contralateral cognate joint and about a 5% chance of a surgical procedure

  7. Radiologic changes of ankle joint after total knee arthroplasty.

    PubMed

    Lee, Jung Hee; Jeong, Bi O

    2012-12-01

    The authors noticed that ankle joint osteoarthritis was not uncommon when lower extremity malalignment, such as a knee varus deformity, was present as a result of severe osteoarthritis of the knee. The purpose of this study was to analyze radiologic changes of the ankle joint after total knee arthroplasty. This study included 142 cases in 110 patients who underwent total knee arthroplasty and were followed for at least 3 years. The varus knee group included 128 cases and the valgus knee group included 14 cases. On anteroposterior standing lower extremity radiographs, varus and valgus angles of the knee were measured preoperatively and at the last follow-up. The angle between the ground surface and the distal tibial plafond as well as the upper talus was also measured. In addition, tibial anterior surface angle, talar tilt, space between the medial malleolar distal tip and the medial articular surface of the talus, and medial tibiotalar joint space of the ankle joint were measured. Out of 142 cases, 50 (35.2%) had arthritis in the ankle before total knee arthroplasty and 31 (21.8%) had newly developed or progressive arthritis after surgery. In particular, the varus knee group demonstrated statistically significant differences in preoperative varus deformity, preoperative talar tilt, and postoperative correction angle between the cases that developed or had progressive arthritis and those that did not show any changes (p < .05). After total knee arthroplasty, arthritis developed or progressed in the ankle of many cases radiographically. In particular, when the preoperative talar tilt increased medial to the ankle or the postoperative correction angle was large, the incidence of arthritis in the ankle joint increased. The authors recommend more cautious follow-up on the symptoms of the ankle joint after total knee arthroplasty.

  8. Preoperative Optimization of Total Joint Arthroplasty Surgical Risk: Obesity.

    PubMed

    Fournier, Matthew N; Hallock, Justin; Mihalko, William M

    2016-08-01

    Obesity is a problem that is increasing in prevalence in the United States and in other countries, and it is a common comorbidity in patients seeking total joint arthroplasty for degenerative musculoskeletal diseases. Obesity, as well as commonly associated comorbidities such as diabetes mellitus, cardiovascular disease, and those contributing to the diagnosis of metabolic syndrome, have been shown to have detrimental effects on total joint arthroplasty outcomes. Although there are effective surgical and nonsurgical interventions which can result in weight loss in these patients, concomitant benefit on arthroplasty outcomes is not clear. Preoperative optimization of surgical risk in obese total joint arthroplasty patients is an important point of intervention to improve arthroplasty outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Total-Body Irradiation Produces Late Degenerative Joint Damage in Rats

    PubMed Central

    Hutchinson, Ian D.; Olson, John; Lindburg, Carl A.; Payne, Valerie; Collins, Boyce; Smith, Thomas L.; Munley, Michael T.; Wheeler, Kenneth T.; Willey, Jeffrey S.

    2014-01-01

    Purpose Premature musculoskeletal joint failure is a major source of morbidity among childhood cancer survivors. Radiation effects on synovial joint tissues of the skeleton are poorly understood. Our goal was to assess long-term changes in the knee joint from skeletally mature rats that received total-body irradiation while skeletal growth was ongoing. Materials and Methods 14 week-old rats were irradiated with 1, 3 or 7 Gy total-body doses of 18 MV x-rays. At 53 weeks of age, structural and compositional changes in knee joint tissues (articular cartilage, subchondral bone, and trabecular bone) were characterized using 7T MRI, nanocomputed tomography (nanoCT), microcomputed tomography (microCT), and histology. Results T2 relaxation times of the articular cartilage were lower after exposure to all doses. Likewise, calcifications were observed in the articular cartilage. Trabecular bone microarchitecture was compromised in the tibial metaphysis at 7 Gy. Mild to moderate cartilage erosion was scored in the 3 and 7 Gy rats. Conclusions Late degenerative changes in articular cartilage and bone were observed after total body irradiation in adult rats exposed prior to skeletal maturity. 7T MRI, microCT, nanoCT, and histology identified potential prognostic indicators of late radiation-induced joint damage. PMID:24885745

  10. Improving transition of care for veterans after total joint replacement.

    PubMed

    Green, Uthona R; Dearmon, Valorie; Taggart, Helen

    2015-01-01

    Patients transitioning from hospital to home are at risk for readmission to the hospital. Readmissions are costly and occur too often. Standardized discharge education processes have shown to decrease readmissions. The purpose of this quality improvement project was to utilize evidence-based practice changes to decrease 30-day all-cause readmissions after total joint replacement. Review of literature revealed that improved discharge education can decrease unnecessary readmissions after discharge. A quality improvement project was developed including standardized total joint replacement discharge education, teach-back education methodology, and improved postdischarge telephone follow-up. The quality improvement project was initiated and outcomes were evaluated. Improving coordination of the discharge process, enhanced education for patients/caregivers, and postdischarge follow-up decreased total joint replacement readmissions.

  11. [Minimally invasive approaches to hip and knee joints for total joint replacement].

    PubMed

    Rittmeister, M; König, D P; Eysel, P; Kerschbaumer, F

    2004-11-01

    The manuscript features the different minimally invasive approaches to the hip for joint replacement. These include medial, anterior, anterolateral, and posterior approaches. The concept of minimally invasive hip arthroplasty makes sense if it is an integral part of a larger concept to lower postoperative morbidity. Besides minimal soft tissue trauma, this concept involves preoperative patient education, preemptive analgesia, and postoperative physiotherapy. It is our belief that minimal incision techniques for the hip are not suited for all patients and all surgeons. The different minimally invasive approaches to the knee joint for implantation of a knee arthroplasty are described and discussed. There have been no studies published yet that fulfill EBM criteria. The data so far show that minimally invasive approaches and implantation techniques for total knee replacements lead to quicker rehabilitation of patients.

  12. Principles of Antibiotic Prophylaxis in Total Joint Arthroplasty: Current Concepts.

    PubMed

    Bosco, Joseph; Bookman, Jared; Slover, James; Edusei, Emmanuel; Levine, Brett

    2016-01-01

    Infection is a rare, serious complication after total joint arthroplasty and constitutes a considerable emotional and financial burden for patients, surgeons, and healthcare systems. Prevention of surgical site and periprosthetic joint infections is crucial. This requires knowledge of the microorganisms that commonly cause these infections, including Staphylococcus species. Selection of the appropriate antibiotic regimen to treat infection remains controversial, but cefazolin and cefuroxime are the most commonly recommended antibiotics for prophylaxis. Appropriate timing of administration before surgery, with redosing performed as needed, can help to ensure optimal antibiotic concentration during surgery. Given the increasing evidence that S aureus colonization is a risk factor for periprosthetic joint infection, an exploration of the potential benefits of preoperative S aureus carrier screening and decolonization protocols is warranted. The use of antibiotic-loaded bone cement in primary total joint arthroplasty and antibiotic powder at wound closure are other controversial topics that require additional research.

  13. The Role of Bariatric Surgery in the Obese Total Joint Arthroplasty Patient.

    PubMed

    Hooper, Jessica M; Deshmukh, Ajit J; Schwarzkopf, Ran

    2018-07-01

    Although bariatric surgery is a proven means of weight loss and treatment of obesity-related comorbidities in morbidly obese patients, it is not yet clear how it affects outcomes after total joint arthroplasty in this high-risk patient population. This article explores the effects of obesity and bariatric surgery on osteoarthritis and total joint arthroplasty, and also discusses the financial and ethical implications of use of bariatric surgery for risk reduction before total joint arthroplasty. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Principles of Antibiotic Prophylaxis in Total Joint Arthroplasty: Current Concepts.

    PubMed

    Bosco, Joseph A; Bookman, Jared; Slover, James; Edusei, Emmanuel; Levine, Brett

    2015-08-01

    Infection is a rare, serious complication following total joint arthroplasty and constitutes a considerable emotional and financial burden for patients, surgeons, and healthcare systems. Prevention of surgical site and periprosthetic joint infections is crucial. This requires knowledge of the microorganisms that commonly cause these infections, including Staphylococcus species. Selection of the appropriate antibiotic regimen to treat infection remains controversial, but cefazolin and cefuroxime are the most commonly recommended antibiotics for prophylaxis. Appropriate timing of administration before surgery, with redosing performed as needed, can help to ensure optimal antibiotic concentration during surgery. Given the increasing evidence that S aureus colonization is a risk factor for periprosthetic joint infection, an exploration of the potential benefits of preoperative S aureus carrier screening and decolonization protocols is warranted. The use of antibiotic-loaded bone cement in primary total joint arthroplasty and antibiotic powder at wound closure are other controversial topics that require additional research. Copyright 2015 by the American Academy of Orthopaedic Surgeons.

  15. The John Charnley Award Paper. The role of joint fluid in the tribology of total joint arthroplasty.

    PubMed

    Mazzucco, Daniel; Spector, Myron

    2004-12-01

    The effect of joint fluid on the tribology (ie, lubrication, friction, and wear) of total hip arthroplasty has not yet been investigated adequately. In the current study, a friction assay was used to assess four hypotheses relating to the effect of human joint fluid and its principal components on the articulation of metal-on-polyethylene. First, joint fluid was found to produce a widely varying amount of friction between cobalt-chromium and polyethylene; this range exceeded the range produced when the articulation was lubricated by water or bovine serum. Second, it was shown that hyaluronic acid, phospholipid, albumin, and gamma-globulin were not acting as boundary lubricants, but that one or more other proteins (as yet unidentified) were responsible for reducing friction in this couple. Third, lower friction was found when oxidized zirconium alloy replaced cobalt-chromium as a bearing surface on polyethylene. Finally, a pilot study suggested that lubricin, which contributes to cartilage-on-cartilage lubrication, is not a protein responsible for the tribological variabiation found among joint fluid samples. The current study showed that joint fluid is a patient factor that influences the tribology of metal-on-polyethylene arthroplasty.

  16. Joint Line Reconstruction in Navigated Total Knee Arthroplasty Revision

    ClinicalTrials.gov

    2012-05-16

    Revision Total Knee Arthroplasty Because of; Loosening; Instability; Impingement; or Other Reasons Accepted as Indications for TKA Exchange.; The Focus is to Determine the Precision of Joint Line Restoration in Navigated vs. Conventional Revision Total Knee Arthroplasty

  17. Regional Anesthesia in Total Joint Arthroplasty: What Is the Evidence?

    PubMed

    Elmofty, Dalia H; Buvanendran, Asokumar

    2017-09-01

    Total joint arthroplasty is one of the most common surgical procedures performed for end-stage osteoarthritis. The increasing demand for knee and hip arthroplasties along with the improvement in life expectancy has created a substantial medical and economic impact on the society. Effective planning of health care for these individuals is vital. The best method for providing anesthesia and analgesia for total joint arthroplasty has not been defined. Yet, emerging evidence suggests that the type of anesthesia can affect morbidity and mortality of patients undergoing these procedures. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Predictors of perioperative blood loss in total joint arthroplasty.

    PubMed

    Park, Jai Hyung; Rasouli, Mohammad R; Mortazavi, S M Javad; Tokarski, Anthony T; Maltenfort, Mitchell G; Parvizi, Javad

    2013-10-02

    UPDATE The print version of this article has errors that have been corrected in the online version of this article. In the Materials and Methods section, the sentence that reads as "During the study period, our institution offered preoperative autologous blood donation to all patients who were scheduling for total joint arthroplasty with a hemoglobin level of no less than 11 mg/dL or a hematocrit level of at least 33%." in the print version now reads as "During the study period, our institution offered preoperative autologous blood donation to all patients who were scheduling for total joint arthroplasty with a hemoglobin level of no less than 11 g/dL or a hematocrit level of at least 33%." in the online version. In Table III, the footnote that reads as "The values are given as the estimate and the standard error in milligrams per deciliter." in the print version now reads as "The values are given as the estimate and the standard error in grams per deciliter." in the online version. Despite advances in surgical and anesthetic techniques, lower-extremity total joint arthroplasty is associated with considerable perioperative blood loss. As predictors of perioperative blood loss and allogenic blood transfusion have not yet been well defined, the purpose of this study was to identify clinical predictors for perioperative blood loss and allogenic blood transfusion in patients undergoing total joint arthroplasty. From 2000 to 2008, all patients undergoing unilateral primary total hip or knee arthroplasty who met the inclusion criteria were enrolled in the study. Perioperative blood loss was calculated with use of a previously validated formula. The predictors of perioperative blood loss and allogenic blood transfusion were identified in a multivariate analysis. Eleven thousand three hundred and seventy-three patients who underwent total joint arthroplasty, including 4769 patients who underwent total knee arthroplasty and 6604 patients who underwent total hip arthroplasty

  19. Academic productivity among fellowship associated adult total joint reconstruction surgeons.

    PubMed

    Khan, Adam Z; Kelley, Benjamin V; Patel, Ankur D; McAllister, David R; Leong, Natalie L

    2017-12-01

    The Hirsch index (h-index) is a measure that evaluates both research volume and quality-taking into consideration both publications and citations of a single author. No prior work has evaluated academic productivity and contributions to the literature of adult total joint replacement surgeons. This study uses h-index to benchmark the academic impact and identify characteristics associated with productivity of faculty members at joint replacement fellowships. Adult reconstruction fellowship programs were obtained via the American Association of Hip and Knee Surgeons website. Via the San Francisco match and program-specific websites, program characteristics (Accreditation Council for Graduate Medical Education approval, academic affiliation, region, number of fellows, fellow research requirement), associated faculty members, and faculty-specific characteristics (gender, academic title, formal fellowship training, years in practice) were obtained. H-index and total faculty publications served as primary outcome measures. Multivariable linear regression determined statistical significance. Sixty-six adult total joint reconstruction fellowship programs were identified: 30% were Accreditation Council for Graduate Medical Education approved and 73% had an academic affiliation. At these institutions, 375 adult reconstruction surgeons were identified; 98.1% were men and 85.3% had formal arthroplasty fellowship training. Average number of publications per faculty member was 50.1 (standard deviation 76.8; range 0-588); mean h-index was 12.8 (standard deviation 13.8; range 0-67). Number of fellows, faculty academic title, years in practice, and formal fellowship training had a significant ( P < .05) positive correlation with both h-index and total publications. The statistical overview presented in this work can help total joint surgeons quantitatively benchmark their academic performance against that of their peers.

  20. Management of the patient with a total joint replacement: the primary care practitioner's role.

    PubMed

    Palmer, L M

    1999-01-01

    The primary care practitioner assumes chief responsibility for patients with arthritis. More than 40 million Americans experience some form of arthritis. Management of the patient with arthritis may include a referral to an orthopedic surgeon for surgical intervention. As estimated, up to 500,000 total joint replacement procedures are performed by orthopedic surgeons each year in the United States. Presurgical evaluation for a total joint replacement is imperative to ensure that the patient can safely undergo this surgical procedure. Postsurgical care of a patient with total joint replacement involves coordinating care with the physical therapist and orthopedic surgeon to ensure adequate follow-through with the recommended rehabilitation program, prophylactic antibiotic coverage, and observation for any complications including infection, deep-vein thrombosis, or loosening of the total-joint prosthesis.

  1. Soft tissue balance changes depending on joint distraction force in total knee arthroplasty.

    PubMed

    Nagai, Kanto; Muratsu, Hirotsugu; Matsumoto, Tomoyuki; Miya, Hidetoshi; Kuroda, Ryosuke; Kurosaka, Masahiro

    2014-03-01

    The influence of joint distraction force on intraoperative soft tissue balance was evaluated using Offset Repo-Tensor® for 78 knees that underwent primary posterior-stabilized total knee arthroplasty. The joint center gap and varus ligament balance were measured between osteotomized surfaces using 20, 40 and 60 lbs of joint distraction force. These values were significantly increased at extension and flexion as the distraction force increased. Furthermore, lateral compartment stiffness was significantly lower than medial compartment stiffness. Thus, larger joint distraction forces led to larger varus ligament balance and joint center gap, because of the difference in soft tissue stiffness between lateral and medial compartments. These findings indicate the importance of the strength of joint distraction force in the assessment of soft tissue balance, especially when using gap-balancing technique. © 2014.

  2. The Measurement Of Total Joint Loosening By X-Ray Photogrammetry

    NASA Astrophysics Data System (ADS)

    Lippert, Frederick G.; Veress, Sandor A.; Tiwari, Rama S.; Harrington, Richard M.

    1980-07-01

    Failure of total joint replacement due to loosening of the composents either between the implant and cement or between the cement and bone is emerging as a late complication with an incidence as high as 20 percent. Loosening may not only cause pain but progressive loss of support for the prosthesis with eventual structural failure. Early diagnosis is important so that revision may be carried when deterioration or pain occurs. No method is currently available which clearly establishes loosening at an early stage except surgical exploration. We have devised a method based on our in vivo photogrammetry studies of patellar tracking patterns using metallic markers placed in bone near both components of the total joint. Stereo x-rays taken with the joint loaded and unloaded are measured for relative motion between the implant and the metallic markers. Laboratory studies using prosthetic hip components mounted in plastic bone have revealed the ability of this method to detect pistoning movements as small as 80 microns. These findings were confirmed by physical measurements.

  3. Joint awareness after total knee arthroplasty is affected by pain and quadriceps strength.

    PubMed

    Hiyama, Y; Wada, O; Nakakita, S; Mizuno, K

    2016-06-01

    There is a growing interest in the use of patient-reported outcomes to provide a more patient-centered view on treatment. Forgetting the artificial joint can be regarded as the goal in joint arthroplasty. The goals of the study were to describe changes in joint awareness in the artificial joint after total knee arthroplasty (TKA), and to determine which factors among pain, knee range of motion (ROM), quadriceps strength, and functional ability affect joint awareness after TKA. Patients undergoing TKA demonstrate changes in joint awareness and joint awareness is associated with pain, knee ROM, quadriceps strength, and functional ability. This prospective cohort study comprised 63 individuals undergoing TKA, evaluated at 1, 6, and 12 months postoperatively. Outcomes included joint awareness assessed using the Forgotten Joint Score (FJS), pain score, knee ROM, quadriceps strength, and functional ability. Fifty-eight individuals completed all postoperative assessments. All measures except for knee extension ROM improved from 1 to 6 months. However, there were no differences in any measures from 6 to 12 months. FJS was affected most greatly by pain at 1 month and by quadriceps strength at 6 and 12 months. Patients following TKA demonstrate improvements in joint awareness and function within 6 months after surgery, but reach a plateau from 6 to 12 months. Quadriceps strength could contribute to this plateau of joint awareness. Prospective cohort study, IV. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  4. Total fixation of cricoarytenoid joint of a patient with rheumatoid arthritis and Hashimoto thyroiditis.

    PubMed

    Stojanović, Stevan P; Zivić, Ljubica; Stojanović, Jasmina; Belić, Branislav

    2010-01-01

    The incidence of cricoarytenoid joint fixation in case of rheumatoid arthritis is 17 to 33%. In later stages of rheumatoid arthritis, a gradual fixation of cricoarytenoid joint develops and both halves of the larynx become less movable which calls for endotracheal intubation; while total fixation of this joint demands surgical tracheotomy. Hashimoto thyroiditis can display symptoms which are difficult to distinguish from the ones present in total fixation of cricoarytenoid joint caused by rheumatoid arthritis. A 60-year-old woman in terminal stage of rheumatoid arthritis and Hashimoto thyroiditis, diagnosed after clinical and other examinations. She was treated for strident breathing with surgical tracheotomy. The microscopic examination of the larynx with the use of laryngoscopic pincers suggested the immovability of the right and very limited movability of the left arytenoid cartilage. A computerized endovideostroboscopy showed only passive vertical vibrating movements of the right vocal cord and irregular vibrations of the left vocal cord. Total fixation of the cricoarytenoid joint can be caused by many pathological processes, but so far references have shown no case of rheumatoid arthritis and Hashimoto thyroiditis. In differential diagnostics, one of many examinations is the microscopic examination of the larynx, but it is very important to determine the movability of the arytenoid cartilage with the use of appropriate instruments in total endotracheal anaesthesia while the patient is fully relaxed. Movements in cricoarytenoid joints in patients with Hashimoto thyroiditis and the same conditions are preserved.

  5. Knee joint distraction compared with total knee arthroplasty: a randomised controlled trial.

    PubMed

    van der Woude, J A D; Wiegant, K; van Heerwaarden, R J; Spruijt, S; Emans, P J; Mastbergen, S C; Lafeber, F P J G

    2017-01-01

    Knee joint distraction (KJD) is a relatively new, knee-joint preserving procedure with the goal of delaying total knee arthroplasty (TKA) in young and middle-aged patients. We present a randomised controlled trial comparing the two. The 60 patients ≤ 65 years with end-stage knee osteoarthritis were randomised to either KJD (n = 20) or TKA (n = 40). Outcomes were assessed at baseline, three, six, nine, and 12 months. In the KJD group, the joint space width (JSW) was radiologically assessed, representing a surrogate marker of cartilage thickness. In total 56 patients completed their allocated treatment (TKA = 36, KJD = 20). All patient reported outcome measures improved significantly over one year (p < 0.02) in both groups. At one year, the TKA group showed a greater improvement in only one of the 16 patient-related outcome measures assessed (p = 0.034). Outcome Measures in Rheumatology-Osteoarthritis Research Society International clinical response was 83% after TKA and 80% after KJD. A total of 12 patients (60%) in the KJD group sustained pin track infections. In the KJD group both mean minimum (0.9 mm, standard deviation (sd) 1.1) and mean JSW (1.2 mm, sd 1.1) increased significantly (p = 0.004 and p = 0.0003). In relatively young patients with end-stage knee osteoarthritis, KJD did not demonstrate inferiority of outcomes at one year when compared with TKA. However, there is a high incidence of pin track infection associated with KJD. Cite this article: Bone Joint J 2017;99-B:51-8. ©2017 The British Editorial Society of Bone & Joint Surgery.

  6. [Joint dislocation after total knee arthroplasty as an ankle fracture complication. Case report].

    PubMed

    Hrubina, M; Skoták, M

    2012-01-01

    Joint dislocation after total knee arthroplasty is a rare complication. It is described as the result of ligamentous instability. Here we report the case of an 82-year-old women who underwent primary total knee arthroplasty (TKA) for advanced primary grade III gonarthrosis. At 3 post-operative months the joint was stable and painless, with radiographic evidence of good TKA alignment and integration. At 4 months the patient suffered injury to the ankle involving a bimalleolar fracture and damage to knee soft tissues. The fracture was surgically treated. Subsequently, dorsal tibial dislocation was manifested. This was managed by individual intramedullary nail arthrodesis. At 8 months following the operation, the knee condition was satisfactory, with rigid arthrodesis and leg shortening of 4 cm. The patient was satisfied because she was free of pain and able to walk. Arthrodesis of the knee joint with an individual nail is an option for a definitive treatment of TKA instability. When other joints, such as ankle or hip joints, are injured, it is recommended to pay attention also to any TKA implanted previously because of potential development of instability or infection.

  7. Development of a Mandibular Motion Simulator for Total Joint Replacement

    PubMed Central

    Celebi, Nukhet; Rohner, E. Carlos; Gateno, Jaime; Noble, Philip C.; Ismaily, Sabir K.; Teichgraeber, John F.; Xia, James J.

    2015-01-01

    Purpose The purpose of this study was to develop a motion simulator capable of recreating and recording the full range of mandibular motions in a cadaveric preparation for an intact temporomandibular joint (TMJ) and after total joint replacement. Material and Methods A human cadaver head was used. Two sets of tracking balls were attached to the forehead and mandible, respectively. Computed tomographic (CT) scan was performed and 3-dimensional CT models of the skull were generated. The cadaver head was then dissected to attach the muscle activation cables and mounted onto the TMJ simulator. Realistic jaw motions were generated through the application of the following muscle forces: lateral pterygoid muscle, suprahyoid depressors (geniohyoid, mylohyoid, and digastric muscles), and elevator muscles. To simulate muscle contraction, cables were inserted into the mandible at the center area of each muscle's attachment. To provide a minimum mouth closing force at the initial position, the elevator muscles were combined at the anterior mandible. During mandibular movement, each motion was recorded using a high-resolution laser scanner. The right TMJ of the same head was reconstructed with a total TMJ prosthesis. The same forces were applied and the jaw motions were recorded again. CT scan was performed and 3-dimensional CT models of the skull with TMJ prosthesis were generated. Results Mandibular motions, before and after TMJ replacement, with and without lateral pterygoid muscle reattachment, were re-created in a cadaveric preparation. The laser-scanned data during the mandibular motion were used to drive 3-dimensional CT models. A movie for each mandibular motion was subsequently created for motion path analysis. Compared with mandibular motion before TMJ replacement, mandibular lateral and protrusive motions after TMJ replacement, with and without lateral pterygoid muscle reattachment, were greatly limited. The jaw motion recorded before total joint replacement was

  8. Body mass and weight thresholds for increased prosthetic joint infection rates after primary total joint arthroplasty.

    PubMed

    Lübbeke, Anne; Zingg, Matthieu; Vu, Diemlan; Miozzari, Hermes H; Christofilopoulos, Panayiotis; Uçkay, Ilker; Harbarth, Stephan; Hoffmeyer, Pierre

    2016-01-01

    Obesity increases the risk of deep infection after total joint arthroplasty (TJA). Our objective was to determine whether there may be body mass index (BMI) and weight thresholds indicating a higher prosthetic joint infection rate. We included all 9,061 primary hip and knee arthroplasties (mean age 70 years, 61% women) performed between March 1996 and December 2013 where the patient had received intravenous cefuroxime (1.5 g) perioperatively. The main exposures of interest were BMI (5 categories: < 24.9, 25-29.9, 30-34.9, 35-39.9, and ≥ 40) and weight (5 categories: < 60, 60-79, 80-99, 100-119, and ≥ 120 kg). Numbers of TJAs according to BMI categories (lowest to highest) were as follows: 2,956, 3,350, 1,908, 633, and 214, respectively. The main outcome was prosthetic joint infection. The mean follow-up time was 6.5 years (0.5-18 years). 111 prosthetic joint infections were observed: 68 postoperative, 16 hematogenous, and 27 of undetermined cause. Incidence rates were similar in the first 3 BMI categories (< 35), but they were twice as high with BMI 35-39.9 (adjusted HR = 2.1, 95% CI: 1.1-4.3) and 4 times higher with BMI ≥ 40 (adjusted HR = 4.2, 95% CI: 1.8-9.7). Weight ≥ 100 kg was identified as threshold for a significant increase in infection from the early postoperative period onward (adjusted HR = 2.1, 95% CI: 1.3-3.6). BMI ≥ 35 or weight ≥ 100 kg may serve as a cutoff for higher perioperative dosage of antibiotics.

  9. Lower limb joint work and joint work contribution during downhill and uphill walking at different inclinations.

    PubMed

    Alexander, Nathalie; Strutzenberger, Gerda; Ameshofer, Lisa Maria; Schwameder, Hermann

    2017-08-16

    Work performance and individual joint contribution to total work are important information for creating training protocols, but were not assessed so far for sloped walking. Therefore, the purpose of this study was to analyze lower limb joint work and joint contribution of the hip, knee and ankle to total lower limb work during sloped walking in a healthy population. Eighteen male participants (27.0±4.7yrs, 1.80±0.05m, 74.5±8.2kg) walked on an instrumented ramp at inclination angles of 0°, ±6°, ±12° and ±18° at 1.1m/s. Kinematic and kinetic data were captured using a motion-capture system (Vicon) and two force plates (AMTI). Joint power curves, joint work (positive, negative, absolute) and each joint's contribution to total lower limb work were analyzed throughout the stance phase using an ANOVA with repeated measures. With increasing inclination positive joint work increased for the ankle and hip joint and in total during uphill walking. Negative joint work increased for each joint and in total work during downhill walking. Absolute work was increased during both uphill (all joints) and downhill (ankle & knee) walking. Knee joint contribution to total negative and absolute work increased during downhill walking while hip and ankle contributions decreased. This study identified, that, when switching from level to a 6° and from 6° to a 12° inclination the gain of individual joint work is more pronounced compared to switching from 12° to an 18° inclination. The results might be used for training recommendations and specific training intervention with respect to sloped walking. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    NASA Astrophysics Data System (ADS)

    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

  11. Surgeons' Perspectives on Premium Implants in Total Joint Arthroplasty.

    PubMed

    Wasterlain, Amy S; Bello, Ricardo J; Vigdorchik, Jonathan; Schwarzkopf, Ran; Long, William J

    2017-09-01

    Declining total joint arthroplasty reimbursement and rising implant prices have led many hospitals to restrict access to newer, more expensive total joint arthroplasty implants. The authors sought to understand arthroplasty surgeons' perspectives on implants regarding innovation, product launch, costs, and cost-containment strategies including surgeon gain-sharing and patient cost-sharing. Members of the International Congress for Joint Reconstruction were surveyed regarding attitudes about implant technology and costs. Descriptive and univariate analyses were performed. A total of 126 surgeons responded from all 5 regions of the United States. Although 76.9% believed new products advance technology in orthopedics, most (66.7%) supported informing patients that new implants lack long-term clinical data and restricting new implants to a small number of investigators prior to widespread market launch. The survey revealed that 66.7% would forgo gain-sharing incentives in exchange for more freedom to choose implants. Further, 76.9% believed that patients should be allowed to pay incremental costs for "premium" implants. Surgeons who believed that premium products advance orthopedic technology were more willing to forgo gain-sharing (P=.040). Surgeons with higher surgical volume (P=.007), those who believed implant companies should be allowed to charge more for new technology (P<.001), and those who supported discussing costs with patients (P=.004) were more supportive of patient cost-sharing. Most arthroplasty surgeons believe technological innovation advances the field but support discussing the "unproven" nature of new implants with patients. Many surgeons support alternative payment models permitting surgeons and patients to retain implant selection autonomy. Most respondents prioritized patient beneficence and surgeon autonomy above personal financial gain. [Orthopedics. 2017; 40(5):e825-e830.]. Copyright 2017, SLACK Incorporated.

  12. A new three-dimensional, print-on-demand temporomandibular prosthetic total joint replacement system: Preliminary outcomes.

    PubMed

    Dimitroulis, George; Austin, Stephen; Sin Lee, Peter Vee; Ackland, David

    2018-05-16

    The aim of this study is to present the preliminary clinical data on the OMX Temporomandibular Joint (TMJ) Prosthetic total joint replacement system. A prospective, cohort, clinical study was undertaken of consecutive adult patients with Category 5 end-stage joint disease who were implanted with the OMX TMJ prosthesis between May 2015 and April 2017. A total of 50 devices were implanted in 38 patients, with 12 patients receiving bilateral prosthetic joints. There were 31 females and 7 males in this cohort, who ranged in age from 20 to 66 years, with a mean of 43.8 years (±14.0 years). Ten of the 50 prosthetic joints (20%) were fully customized, while the remaining were patient matched using virtual planning software. Based on a mean follow-up period of 15.3 months (range 12-24 months) following the TMJ total joint replacement, preliminary results suggest the OMX TMJ prosthesis has made a positive impact on clinical outcomes, with a mean 74.4% reduction in joint pain levels and significant improvements (p < 0.05) in jaw function as measured by the visual analogue scales for mouth opening (30.8%), diet (77.1%), and function (59.2%). No device failures were reported during the study period. This study suggests that the print-on-demand OMX TMJ prosthesis, designed for rapid delivery of both patient-matched and fully customize devices, represents a safe, reliable and versatile implantable joint replacement system for the treatment of category 5 end-stage TMJ disease. Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  13. Body mass and weight thresholds for increased prosthetic joint infection rates after primary total joint arthroplasty

    PubMed Central

    Lübbeke, Anne; Zingg, Matthieu; Vu, Diemlan; Miozzari, Hermes H; Christofilopoulos, Panayiotis; Uçkay, Ilker; Harbarth, Stephan; Hoffmeyer, Pierre

    2016-01-01

    Background and purpose — Obesity increases the risk of deep infection after total joint arthroplasty (TJA). Our objective was to determine whether there may be body mass index (BMI) and weight thresholds indicating a higher prosthetic joint infection rate. Patients and methods — We included all 9,061 primary hip and knee arthroplasties (mean age 70 years, 61% women) performed between March 1996 and December 2013 where the patient had received intravenous cefuroxime (1.5 g) perioperatively. The main exposures of interest were BMI (5 categories: < 24.9, 25–29.9, 30–34.9, 35–39.9, and ≥ 40) and weight (5 categories: < 60, 60–79, 80–99, 100–119, and ≥ 120 kg). Numbers of TJAs according to BMI categories (lowest to highest) were as follows: 2,956, 3,350, 1,908, 633, and 214, respectively. The main outcome was prosthetic joint infection. The mean follow-up time was 6.5 years (0.5–18 years). Results — 111 prosthetic joint infections were observed: 68 postoperative, 16 hematogenous, and 27 of undetermined cause. Incidence rates were similar in the first 3 BMI categories (< 35), but they were twice as high with BMI 35–39.9 (adjusted HR = 2.1, 95% CI: 1.1–4.3) and 4 times higher with BMI ≥ 40 (adjusted HR = 4.2, 95% CI: 1.8–9.7). Weight ≥ 100 kg was identified as threshold for a significant increase in infection from the early postoperative period onward (adjusted HR = 2.1, 95% CI: 1.3–3.6). Interpretation — BMI ≥ 35 or weight ≥ 100 kg may serve as a cutoff for higher perioperative dosage of antibiotics. PMID:26731633

  14. Is There an Association Between Smoking Status and Prosthetic Joint Infection After Primary Total Joint Arthroplasty?

    PubMed

    Gonzalez, Amanda I; Luime, Jolanda J; Uçkay, Ilker; Hannouche, Didier; Hoffmeyer, Pierre; Lübbeke, Anne

    2018-02-23

    Recent reports highlighted the association between smoking and higher risk of postsurgical infections. The aim was to compare the incidence of prosthetic joint infection after primary total joint arthroplasty (TJA) according to smoking status. A prospective hospital registry-based cohort study was performed including all primary knee and hip TJAs performed between March 1996 and December 2013. Smoking status preoperatively was classified into never, former, and current smoker. Incidence rates and hazard ratios (HRs) for prosthetic joint infection according to smoking status were assessed within the first year and beyond. We included 8559 primary TJAs (mean age 69.5 years), and median follow-up was 67 months. There were 5722 never, 1315 former, and 1522 current smokers. Incidence rates of infection within the first year for never, former, and current smokers were, respectively, 4.7, 10.1, and 10.9 cases/1000 person-years, comparing ever vs never smokers, crude and adjusted HRs were 2.35 (95% confidence interval [CI] 1.39-3.98) and 1.8 (95% CI 1.04-3.2). Beyond the first year, crude and adjusted HRs were 1.37 (95% CI 0.78-2.39) and 1.12 (95% CI 0.61-2.04). Smoking increased the infection risk about 1.8 times after primary hip or knee TJA in both current and former smokers. Beyond the first year, the infection risk was similar to never smokers. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Protocol for concomitant temporomandibular joint custom-fitted total joint reconstruction and orthognathic surgery utilizing computer-assisted surgical simulation.

    PubMed

    Movahed, Reza; Teschke, Marcus; Wolford, Larry M

    2013-12-01

    Clinicians who address temporomandibular joint (TMJ) pathology and dentofacial deformities surgically can perform the surgery in 1 stage or 2 separate stages. The 2-stage approach requires the patient to undergo 2 separate operations and anesthesia, significantly prolonging the overall treatment. However, performing concomitant TMJ and orthognathic surgery (CTOS) in these cases requires careful treatment planning and surgical proficiency in the 2 surgical areas. This article presents a new treatment protocol for the application of computer-assisted surgical simulation in CTOS cases requiring reconstruction with patient-fitted total joint prostheses. The traditional and new CTOS protocols are described and compared. The new CTOS protocol helps decrease the preoperative workup time and increase the accuracy of model surgery. Copyright © 2013 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  16. Joint Disorders - Multiple Languages

    MedlinePlus

    ... a new window. Arabic (العربية) Expand Section Home Care After Total Joint Replacement - العربية (Arabic) Bilingual PDF Health Information Translations Bosnian (bosanski) Expand Section Home Care After Total Joint Replacement - bosanski (Bosnian) Bilingual PDF Health Information ...

  17. HiL simulation in biomechanics: a new approach for testing total joint replacements.

    PubMed

    Herrmann, Sven; Kaehler, Michael; Souffrant, Robert; Rachholz, Roman; Zierath, János; Kluess, Daniel; Mittelmeier, Wolfram; Woernle, Christoph; Bader, Rainer

    2012-02-01

    Instability of artificial joints is still one of the most prevalent reasons for revision surgery caused by various influencing factors. In order to investigate instability mechanisms such as dislocation under reproducible, physiologically realistic boundary conditions, a novel test approach is introduced by means of a hardware-in-the-loop (HiL) simulation involving a highly flexible mechatronic test system. In this work, the underlying concept and implementation of all required units is presented enabling comparable investigations of different total hip and knee replacements, respectively. The HiL joint simulator consists of two units: a physical setup composed of a six-axes industrial robot and a numerical multibody model running in real-time. Within the multibody model, the anatomical environment of the considered joint is represented such that the soft tissue response is accounted for during an instability event. Hence, the robot loads and moves the real implant components according to the information provided by the multibody model while transferring back the position and resisting moment recorded. Functionality of the simulator is proved by testing the underlying control principles, and verified by reproducing the dislocation process of a standard total hip replacement. HiL simulations provide a new biomechanical testing tool for analyzing different joint replacement systems with respect to their instability behavior under realistic movements and physiological load conditions. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  18. Long-Acting Opioid Use Independently Predicts Perioperative Complication in Total Joint Arthroplasty.

    PubMed

    Sing, David C; Barry, Jeffrey J; Cheah, Jonathan W; Vail, Thomas P; Hansen, Erik N

    2016-09-01

    Opioid therapy is an increasingly used modality for treatment of musculoskeletal pain despite multiple associated risks. The purpose of this study was to evaluate how preoperative opioid use affects early outcomes after total joint arthroplasty. A total of 174 patients undergoing total joint arthroplasty were matched by age, gender, and procedure into 3 groups stratified by preoperative opioid use (nonuser, short acting [eg, Vicodin], long acting [eg, Oxycontin]). Compared to nonusers, preoperative long-acting use was associated with increased postoperative mean opioid consumption (46 mg vs 366 mg mean morphine equivalents, P < .001) and independently predicted complications within 90 days (odds ratio: 6.15, confidence interval: [1.46, 25.95], P = .013). Preoperative opioid use should be disclosed as a risk factor for complication to patients and taken into consideration by physicians before initiating opioid management. Copyright © 2016 Elsevier Inc. All rights reserved.

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

    PubMed

    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

  20. Risk factors for renal dysfunction after total knee joint replacement.

    PubMed

    Hassan, Basim K; Sahlström, Arne; Dessau, Ram B

    2015-12-01

    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 knee joint replacement. A retrospective study was conducted among 702 consecutive primary knee joint replacements performed between January 2009 and December 2012 in our department. Increased postoperative serum creatinine was considered indicative of postoperative renal injury according to RIFLE criteria. Sixty three patients (9.7%) had significant moderate or severe postoperative renal dysfunction in which 8 patients (1.2%) ended with severe and permanent renal impairment. Advanced age, low intraoperative blood pressure, hypertension, general anaesthesia, and prophylactic dicloxacillin were identified as significant risk factors. Male gender and BMI were independent risk factors for postoperative increase in serum creatinine. Smoking, female gender, diabetes mellitus and duration of surgery were not identified as significant risk factors.

  1. Obesity: The Modifiable Risk Factor in Total Joint Arthroplasty.

    PubMed

    Bookman, Jared S; Schwarzkopf, Ran; Rathod, Parthiv; Iorio, Richard; Deshmukh, Ajit J

    2018-07-01

    Obesity is an epidemic in the health care system. Obesity poses several challenges and raises unique issues for the arthroplasty surgeon. Obese patients are at higher risk for infection and dislocation. Additionally, obese patients have poorer implant survivorship and functional scores postoperatively. Obesity is a modifiable risk factor and weight loss preoperatively should be strongly considered. Obese patients must be counseled so that they have realistic expectations after total joint arthroplasty. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. In vitro method for assessing the biomechanics of the patellofemoral joint following total knee arthroplasty.

    PubMed

    Coles, L G; Gheduzzi, S; Miles, A W

    2014-12-01

    The patellofemoral joint is a common site of pain and failure following total knee arthroplasty. A contributory factor may be adverse patellofemoral biomechanics. Cadaveric investigations are commonly used to assess the biomechanics of the joint, but are associated with high inter-specimen variability and often cannot be carried out at physiological levels of loading. This study aimed to evaluate the suitability of a novel knee simulator for investigating patellofemoral joint biomechanics. This simulator specifically facilitated the extended assessment of patellofemoral joint biomechanics under physiological levels of loading. The simulator allowed the knee to move in 6 degrees of freedom under quadriceps actuation and included a simulation of the action of the hamstrings. Prostheses were implanted on synthetic bones and key soft tissues were modelled with a synthetic analogue. In order to evaluate the physiological relevance and repeatability of the simulator, measurements were made of the quadriceps force and the force, contact area and pressure within the patellofemoral joint using load cells, pressure-sensitive film, and a flexible pressure sensor. The results were in agreement with those previously reported in the literature, confirming that the simulator is able to provide a realistic physiological loading situation. Under physiological loading, average standard deviations of force and area measurements were substantially lower and comparable to those reported in previous cadaveric studies, respectively. The simulator replicates the physiological environment and has been demonstrated to allow the initial investigation of factors affecting patellofemoral biomechanics following total knee arthroplasty. © IMechE 2014.

  3. Mechanical Prophylaxis after Lower Extremity Total Joint Arthroplasty: A Review.

    PubMed

    Chughtai, Morad; Newman, Jared M; Solow, Max; Davidson, Iyooh U; Sodhi, Nipun; Gaal, Benjamin; Khlopas, Anton; Sultan, Assem A; Mont, Michael A

    2017-12-22

    Venous thromboembolism (VTE) is a serious complication that can occur after total hip and knee arthroplasty, and can potentially lead to significant morbidity and even mortality. While various modalities have been used to prevent VTE development, the medications can be associated with a number of adverse events. Therefore, mechanical prophylaxis with pumps and compressive devices has been used more frequently alone, or in combination, with medications. Therefore, the purpose of this study was to review the current literature on mechanical prophylaxis for VTEs after lower extremity total joint arthroplasty. Specifically, we reviewed mechanical prophylaxis after: 1) total hip arthroplasty and 2) total knee arthroplasty.

  4. MR Imaging with Metal-suppression Sequences for Evaluation of Total Joint Arthroplasty.

    PubMed

    Talbot, Brett S; Weinberg, Eric P

    2016-01-01

    Metallic artifact at orthopedic magnetic resonance (MR) imaging continues to be an important problem, particularly in the realm of total joint arthroplasty. Complications often follow total joint arthroplasty and can be expected for a small percentage of all implanted devices. Postoperative complications involve not only osseous structures but also adjacent soft tissues-a highly problematic area at MR imaging because of artifacts from metallic prostheses. Without special considerations, susceptibility artifacts from ferromagnetic implants can unacceptably degrade image quality. Common artifacts include in-plane distortions (signal loss and signal pileup), poor or absent fat suppression, geometric distortion, and through-section distortion. Basic methods to reduce metallic artifacts include use of spin-echo or fast spin-echo sequences with long echo train lengths, short inversion time inversion-recovery (STIR) sequences for fat suppression, a high bandwidth, thin section selection, and an increased matrix. With care and attention to the alloy type (eg, titanium, cobalt-chromium, stainless steel), orientation of the implant, and magnetic field strength, as well as use of proprietary and nonproprietary metal-suppression techniques, previously nondiagnostic studies can yield key diagnostic information. Specifically, sequences such as the metal artifact reduction sequence (MARS), WARP (Siemens Healthcare, Munich, Germany), slice encoding for metal artifact correction (SEMAC), and multiacquisition with variable-resonance image combination (MAVRIC) can be optimized to reveal pathologic conditions previously hidden by periprosthetic artifacts. Complications of total joint arthroplasty that can be evaluated by using MR imaging with metal-suppression sequences include pseudotumoral conditions such as metallosis and particle disease, infection, aseptic prosthesis loosening, tendon injury, and muscle injury. ©RSNA, 2015.

  5. Strength Variation of Parachute Joints

    NASA Technical Reports Server (NTRS)

    Mollmann, Catherine

    2017-01-01

    A parachute joint is defined as a location where a component is sewn or connected to another component. During the design and developmental phase of a parachute system, the joints for each structural component are isolated and tested through a process called seam and joint testing. The objective of seam and joint testing is to determine the degradation on a single component due to interaction with other components; this data is then used when calculating the margin of safety for that component. During the engineering developmental phase of CPAS (Capsule Parachute Assembly System), the parachute system for the NASA Orion Crew Module, testing was completed for every joint of the six subsystems: the four parachutes (main, drogue, pilot, and FBCP [forward bay cover parachute]), the retention release bridle, and the retention panels. The number of joint tests for these subsystems totaled 92, which provides a plethora of data and results for further analysis. In this paper, the data and results of these seam and joint tests are examined to determine the effects, if any, of different operators and sewing machines on the strength of parachute joints. Other variables are also studied to determine their effect on joint strength, such as joint complexity, joint strength magnitude, material type, and material construction. Findings reveal that an optimally-run seam and joint test program could result in an increased understanding of the structure of the parachute; this should lead to a parachute built with optimal components, potentially saving system weight and volume.

  6. Generalised joint hypermobility and knee joint hypermobility: prevalence, knee joint symptoms and health-related quality of life in a Danish adult population.

    PubMed

    Junge, Tina; Henriksen, Peter; Hansen, Sebrina; Østengaard, Lasse; Golightly, Yvonne M; Juul-Kristensen, Birgit

    2017-10-27

    Several biomechanical factors, such as knee joint hypermobility (KJH), are suggested to play a role in the etiology of knee joint symptoms and knee osteoarthritis. Nevertheless, the prevalence or consequences of KJH solely or included in the classification of generalized joint hypermobility (GJHk) is unknown for a general population. Therefore, the objectives were to report the prevalence of self-reported GJHk and KJH, as well as the association of these conditions to knee joint symptoms, severity and duration of symptoms, and health-related quality of life (HRQoL) in a Danish adult population. This study is a cross-sectional population-based survey of 2056 Danish adults. Respondents received online questionnaires of GJHk and KJH, knee joint symptoms, the severity and duration of these, as well as HRQoL. Total response rate was 49% (n = 1006). The prevalence of self-reported GJHk and KJH was 13% and 23%, mostly representing women. More than half of the respondents with GJHk and KJH had knee joint symptoms. The odds for reporting knee joint symptoms, severity of knee joint symptoms and duration of knee joint symptoms were twice as high for respondents with GJHk and KJH. Respondents with GJHk and KJH reported lower HRQoL. GJHk and KJH were frequently reported in the Danish adult population, mostly in women. Respondents with GJHk and KJH were two times more likely to report knee joint-related symptoms such as pain, reduced performance of usual activity and lower HRQoL. The impact of these conditions on HRQoL is comparable with knee osteoarthritis. © 2017 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.

  7. Dual-joint modeling for estimation of total knee replacement contact forces during locomotion.

    PubMed

    Hast, Michael W; Piazza, Stephen J

    2013-02-01

    Model-based estimation of in vivo contact forces arising between components of a total knee replacement is challenging because such forces depend upon accurate modeling of muscles, tendons, ligaments, contact, and multibody dynamics. Here we describe an approach to solving this problem with results that are tested by comparison to knee loads measured in vivo for a single subject and made available through the Grand Challenge Competition to Predict in vivo Tibiofemoral Loads. The approach makes use of a "dual-joint" paradigm in which the knee joint is alternately represented by (1) a ball-joint knee for inverse dynamic computation of required muscle controls and (2) a 12 degree-of-freedom (DOF) knee with elastic foundation contact at the tibiofemoral and patellofemoral articulations for forward dynamic integration. Measured external forces and kinematics were applied as a feedback controller and static optimization attempted to track measured knee flexion angles and electromyographic (EMG) activity. The resulting simulations showed excellent tracking of knee flexion (average RMS error of 2.53 deg) and EMG (muscle activations within ±10% envelopes of normalized measured EMG signals). Simulated tibiofemoral contact forces agreed qualitatively with measured contact forces, but their RMS errors were approximately 25% of the peak measured values. These results demonstrate the potential of a dual-joint modeling approach to predict joint contact forces from kinesiological data measured in the motion laboratory. It is anticipated that errors in the estimation of contact force will be reduced as more accurate subject-specific models of muscles and other soft tissues are developed.

  8. Understanding and Controlling Cost in Total Joint Arthroplasty.

    PubMed

    Alvarado, Carlos M; Bosco, Joseph

    2015-06-01

    Total joint arthrosplasty (TJA) is both a commonly performed successful intervention and an expensive procedure.As our population ages, the expense of these interventions is expected to grow and hence its impact on healthcare costs will also grow. To ensure that TJA is available to all those who would benefit, it is incumbent that healthcare providers control the cost of these procedures. As orthopaedic surgeons, we must be at the forefront of this effort. The purpose of this review is to outline strategies to control or even decrease TJA cost without negatively affecting outcomes.This concept is at the center of value-based medicine and must guide our decision-making processes.

  9. Second-site prosthetic joint infection in patients with multiple prosthetic joints.

    PubMed

    Clesham, Kevin; Hughes, Andrew J; O' hEireamhoin, Sven; Fleming, Catherine; Murphy, Colin G

    2018-04-10

    Prosthetic joint infections (PJIs) are among the most serious complications in arthroplasty. A second-site PJI in patients with multiple prosthetic joints increases morbidity, with many requiring further revision procedures. We aimed to establish why some patients with multiple joints develop second-site infections. Our institution's arthroplasty database was reviewed from 2004 to 2017. All PJIs were identified, and all patients with more than one prosthetic joint in situ were included. We recorded risk factors, causative organisms, number of procedures and length of stay. Forty-four patients meeting the criteria were identified. Four patients (9.1%) developed second-site infection. Eight patients (18.2%) developed re-infection of the primary PJI. Positive MRSA carrier status and PJI of a total knee replacement were associated with an increased risk of a second episode of infection. Patients who developed further infection had more frequent admission and longer lengths of stay than isolated PJIs. Higher morbidity and use of hospital resources are associated with this cohort of patients. PJIs in total knee replacements and positive MRSA status are associated with higher rates of second infection. Identifying this vulnerable cohort of patients at an early stage is critical to ensure measures are taken to reduce the risks of further infection.

  10. Determination of representative dimension parameter values of Korean knee joints for knee joint implant design.

    PubMed

    Kwak, Dai Soon; Tao, Quang Bang; Todo, Mitsugu; Jeon, Insu

    2012-05-01

    Knee joint implants developed by western companies have been imported to Korea and used for Korean patients. However, many clinical problems occur in knee joints of Korean patients after total knee joint replacement owing to the geometric mismatch between the western implants and Korean knee joint structures. To solve these problems, a method to determine the representative dimension parameter values of Korean knee joints is introduced to aid in the design of knee joint implants appropriate for Korean patients. Measurements of the dimension parameters of 88 male Korean knee joint subjects were carried out. The distribution of the subjects versus each measured parameter value was investigated. The measured dimension parameter values of each parameter were grouped by suitable intervals called the "size group," and average values of the size groups were calculated. The knee joint subjects were grouped as the "patient group" based on "size group numbers" of each parameter. From the iterative calculations to decrease the errors between the average dimension parameter values of each "patient group" and the dimension parameter values of the subjects, the average dimension parameter values that give less than the error criterion were determined to be the representative dimension parameter values for designing knee joint implants for Korean patients.

  11. Cytokine mRNA expression in synovial fluid of affected and contralateral stifle joints and the left shoulder joint in dogs with unilateral disease of the stifle joint.

    PubMed

    de Bruin, Tanya; de Rooster, Hilde; van Bree, Henri; Duchateau, Luc; Cox, Eric

    2007-09-01

    To examine mRNA expression of cytokines in synovial fluid (SF) cells from dogs with cranial cruciate ligament (CrCL) rupture and medial patellar luxation (MPL) and determine mRNA expression for 3 joints (affected stifle, unaffected contralateral stifle, and left shoulder joints) in dogs with unilateral CrCL rupture. 29 stifle joints with CrCL rupture (29 dogs), 8 stifle joints with MPL (7 dogs), and 24 normal stifle joints (16 clinically normal dogs). Immediately before reconstructive surgery, SF was aspirated from the cruciate-deficient stifle joint or stifle joint with MPL. Fourteen of 29 dogs had unilateral CrCL rupture; SF was also aspirated from the unaffected contralateral stifle joint and left shoulder joint. Those 14 dogs were examined 6 and 12 months after reconstructive surgery. Total RNA was extracted from SF cells and reverse transcription-PCR assay was performed to obtain cDNA. Canine-specific cytokine mRNA expression was determined by use of a real-time PCR assay. Interleukin (IL)-8 and -10 and interferon-gamma expression differed significantly between dogs with arthropathies and dogs with normal stifle joints. For the 14 dogs with unilateral CrCL rupture, a significant difference was found for IL-8 expression. Before reconstructive surgery, IL-8 expression differed significantly between the affected stifle joint and left shoulder joint or contralateral stifle joint. Six months after surgery, IL-8 expression was significantly increased in the unaffected contralateral stifle joint, compared with the shoulder joint. No conclusions can be made regarding the role of the examined cytokines in initiation of CrCL disease.

  12. Friction in Total Hip Joint Prosthesis Measured In Vivo during Walking

    PubMed Central

    Damm, Philipp; Dymke, Joern; Ackermann, Robert; Bender, Alwina; Graichen, Friedmar; Halder, Andreas; Beier, Alexander; Bergmann, Georg

    2013-01-01

    Friction-induced moments and subsequent cup loosening can be the reason for total hip joint replacement failure. The aim of this study was to measure the in vivo contact forces and friction moments during walking. Instrumented hip implants with Al2O3 ceramic head and an XPE inlay were used. In vivo measurements were taken 3 months post operatively in 8 subjects. The coefficient of friction was calculated in 3D throughout the whole gait cycle, and average values of the friction-induced power dissipation in the joint were determined. On average, peak contact forces of 248% of the bodyweight and peak friction moments of 0.26% bodyweight times meter were determined. However, contact forces and friction moments varied greatly between individuals. The friction moment increased during the extension phase of the joint. The average coefficient of friction also increased during this period, from 0.04 (0.03 to 0.06) at contralateral toe off to 0.06 (0.04 to 0.08) at contralateral heel strike. During the flexion phase, the coefficient of friction increased further to 0.14 (0.09 to 0.23) at toe off. The average friction-induced power throughout the whole gait cycle was 2.3 W (1.4 W to 3.8 W). Although more parameters than only the synovia determine the friction, the wide ranges of friction coefficients and power dissipation indicate that the lubricating properties of synovia are individually very different. However, such differences may also exist in natural joints and may influence the progression of arthrosis. Furthermore, subjects with very high power dissipation may be at risk of thermally induced implant loosening. The large increase of the friction coefficient during each step could be caused by the synovia being squeezed out under load. PMID:24260114

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

    PubMed

    Damm, Philipp; Dymke, Joern; Ackermann, Robert; Bender, Alwina; Graichen, Friedmar; Halder, Andreas; Beier, Alexander; Bergmann, Georg

    2013-01-01

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

  14. Tribology and total hip joint replacement: current concepts in mechanical simulation.

    PubMed

    Affatato, S; Spinelli, M; Zavalloni, M; Mazzega-Fabbro, C; Viceconti, M

    2008-12-01

    Interest in the rheology and effects of interacting surfaces is as ancient as man. This subject can be represented by a recently coined word: tribology. This term is derived from the Greek word "tribos" and means the "science of rubbing". Friction, lubrication, and wear mechanism in the common English language means the precise field of interest of tribology. Wear of total hip prosthesis is a significant clinical problem that involves, nowadays, a too high a number of patients. In order to acquire further knowledge on the tribological phenomena that involve hip prosthesis wear tests are conducted on employed materials to extend lifetime of orthopaedic implants. The most basic type of test device is the material wear machine, however, a more advanced one may more accurately reproduce some of the in vivo conditions. Typically, these apparatus are called simulators, and, while there is no absolute definition of a joint simulator, its description as a mechanical rig used to test a joint replacement, under conditions approximating those occurring in the human body, is acceptable. Simulator tests, moreover, can be used to conduct accelerated protocols that replicate/simulate particularly extreme conditions, thus establishing the limits of performance for the material. Simulators vary in their level of sophistication and the international literature reveals many interpretations of the design of machines used for joint replacement testing. This paper aims to review the current state of the art of the hip joint simulators worldwide. This is specified through a schematic overview by describing, in particular, constructive solutions adopted to reproduce in vivo conditions. An exhaustive commentary on the evolution and actually existing simulation standards is proposed by the authors. The need of a shared protocol among research laboratories all over the world could lead to a consensus conference.

  15. Current Trends in Discharge Disposition and Post-discharge Care After Total Joint Arthroplasty.

    PubMed

    Tarity, T David; Swall, Marion M

    2017-09-01

    The purpose of this manuscript is to review published literature over the last 5 years to assess recent trends and influencing factors regarding discharge disposition and post-discharge care following total joint arthroplasty. We evaluated instruments proposed to predict a patient's discharge disposition and summarize reports investigating the safety in sending more patients home by reviewing complications and readmission rates. Current literature supports decreased length of hospital stay and increased discharge to home with cost savings and stable readmission rates. Surgeons with defined clinical pathways and those who shape patient expectations may more effectively control costs than those without defined pathways. Further research is needed analyzing best practices in care coordination, managing patient expectations, and cost-effective analysis of home discharge while at the same time ensuring patient outcomes are optimized following total joint arthroplasty.

  16. Degenerative joint disease: multiple joint involvement in young and mature dogs.

    PubMed

    Olsewski, J M; Lust, G; Rendano, V T; Summers, B A

    1983-07-01

    Radiologic, pathologic, and ancillary methods were used to determine the occurrence of degenerative joint disease involving multiple joints of immature and adult dogs. Animals were selected for the development of hip joint dysplasia and chronic degenerative joint disease. Of disease-prone dogs, 82% (45 of 55 dogs) had radiologic changes, indicative of hip dysplasia, by 1 year of age. At necropsy, more abnormal joints were identified than by radiographic examination. Among 92 dogs between 3 to 11 months of age that had joint abnormalities, 71% had hip joint involvement; 38%, shoulder joint involvement; 22%, stifle joint involvement; and 40% had multiple joint involvement. Polyarthritis was asymptomatic and unexpected. Radiographic examination of older dogs also revealed evidence of degenerative joint disease in many joints. Multiple joint involvement was substantiated at necropsy of young and mature dogs. A similar pattern of polyarticular osteoarthritis was revealed in a survey (computer search) of necropsy reports from medical case records of 100 adult and elderly dogs. Usually, the joint disease was an incidental observation, unrelated to the clinical disease or to the cause of death. The frequent occurrence of degenerative changes in several joints of dogs aged 6 months to 17 years indicated that osteoarthritis may be progressive in these joints and raises the possibility that systemic factors are involved in the disease process.

  17. Dissimilar metals joint evaluation

    NASA Technical Reports Server (NTRS)

    Wakefield, M. E.; Apodaca, L. E.

    1974-01-01

    Dissimilar metals tubular joints between 2219-T851 aluminum alloy and 304L stainless steel were fabricated and tested to evaluate bonding processes. Joints were fabricated by four processes: (1) inertia (friction) weldings, where the metals are spun and forced together to create the weld; (2) explosive welding, where the metals are impacted together at high velocity; (3) co-extrusion, where the metals are extruded in contact at high temperature to promote diffusion; and (4) swaging, where residual stresses in the metals after a stretching operation maintain forced contact in mutual shear areas. Fifteen joints of each type were prepared and evaluated in a 6.35 cm (2.50 in.) O.D. size, with 0.32 cm (0.13 in.) wall thickness, and 7.6 cm (3.0 in) total length. The joints were tested to evaluate their ability to withstand pressure cycle, thermal cycle, galvanic corrosion and burst tests. Leakage tests and other non-destructive test techniques were used to evaluate the behavior of the joints, and the microstructure of the bond areas was analyzed.

  18. Higher forgotten joint score for fixed-bearing than for mobile-bearing total knee arthroplasty.

    PubMed

    Thienpont, E; Zorman, D

    2016-08-01

    To compare the postoperative subjective outcome for fixed- and mobile-bearing total knee arthroplasty (TKA) by using the forgotten joint score (FJS-12), a new patient-reported outcome score of 12 questions evaluating the potential of a patient to forget about his operated joint. The hypothesis of this study was that a mobile-bearing TKA would have a higher level of forgotten joint than a fixed-bearing model of the same design. A retrospective cohort study was conducted in 100 patients who underwent TKA at least 1 year [mean (SD) 18 (5) months] before with either a fixed-bearing (N = 50) or a mobile-bearing (N = 50) TKA from the same implant family. Clinical outcome was evaluated with the knee society score and patient-reported outcome with the forgotten joint score. No difference was observed for demographics in between both study groups. The mean (SD) postoperative FJS-12 for the fixed-bearing TKA was 71 (28) compared to a mean (SD) of 56.5 (30) for the mobile-bearing TKA. The clinical relevance of the present retrospective study is that it shows for the first time a significant difference between fixed- and mobile-bearing TKA by using a new patient-reported outcome score. The hypothesis that mobile-bearing TKA would have a higher degree of forgotten joint than a fixed-bearing TKA could not be confirmed. A level I prospective study should be set up to objectivise these findings. IV.

  19. Post-acute care disparities in total joint arthroplasty.

    PubMed

    Lan, Roy H; Kamath, Atul F

    2017-09-01

    Understanding the socioeconomic factors that influence hospitalization and post-discharge metrics after joint replacement is important for identifying key areas of improvement in the delivery of orthopaedic care. An institutional administrative data set of 2869 patients from an academic arthroplasty referral center was analyzed to quantify the relationship between socioeconomic factors and post-acute rehabilitation care received, length of stay, and cost of care. The study used International Classification of Disease, ninth edition coding in order to identify cohorts of patients who received joint arthroplasty of the knee and hip between January 2007 and May 2015. The study found that females (odds ratio [OR], 2.07; 95% confidence interval [CI], 1.74-2.46), minorities (OR, 2.11; 95% CI, 1.78-2.51), and non-private insurance holders (OR, 1.56; 95% CI, 1.26-1.94) were more likely to be assigned to institutional care after discharge. The study also found that minorities (OR, 1.45; 95% CI, 1.24-1.70) and non-private insurance holders (OR, 1.43; 95% CI, 1.16-1.77) are more likely to exhibit longer length of stay. Mean charges were higher for males when compared to females ($80,010 vs $74,855; P < .001), as well as total costs ($19,910 vs $18,613; P  = .001). Socioeconomic factors such as gender, race, and insurance status should be further explored with respect to healthcare policies seeking to influence quality of care and health outcomes.

  20. Determination of Parachute Joint Factors using Seam and Joint Testing

    NASA Technical Reports Server (NTRS)

    Mollmann, Catherine

    2015-01-01

    This paper details the methodology for determining the joint factor for all parachute components. This method has been successfully implemented on the Capsule Parachute Assembly System (CPAS) for the NASA Orion crew module for use in determining the margin of safety for each component under peak loads. Also discussed are concepts behind the joint factor and what drives the loss of material strength at joints. The joint factor is defined as a "loss in joint strength...relative to the basic material strength" that occurs when "textiles are connected to each other or to metals." During the CPAS engineering development phase, a conservative joint factor of 0.80 was assumed for each parachute component. In order to refine this factor and eliminate excess conservatism, a seam and joint testing program was implemented as part of the structural validation. This method split each of the parachute structural joints into discrete tensile tests designed to duplicate the loading of each joint. Breaking strength data collected from destructive pull testing was then used to calculate the joint factor in the form of an efficiency. Joint efficiency is the percentage of the base material strength that remains after degradation due to sewing or interaction with other components; it is used interchangeably with joint factor in this paper. Parachute materials vary in type-mainly cord, tape, webbing, and cloth -which require different test fixtures and joint sample construction methods. This paper defines guidelines for designing and testing samples based on materials and test goals. Using the test methodology and analysis approach detailed in this paper, the minimum joint factor for each parachute component can be formulated. The joint factors can then be used to calculate the design factor and margin of safety for that component, a critical part of the design verification process.

  1. Serum and Wound Vancomycin Levels After Intrawound Administration in Primary Total Joint Arthroplasty.

    PubMed

    Johnson, Jeremiah D; Nessler, Joseph M; Horazdovsky, Ryan D; Vang, Sandy; Thomas, Avis J; Marston, Scott B

    2017-03-01

    Periprosthetic joint infection is the most common cause of readmissions after total joint arthroplasty (TJA). Intrawound vancomycin powder (VP) has reduced infection rates in spine surgery; however, there are no data regarding VP in primary TJA. Thirty-four TJA patients received 2 g of VP intraoperatively to investigate VP's pharmacokinetics. Serum and wound concentrations were measured at multiple intervals over 24 hours after closure. All serum concentrations were subtherapeutic (<15μg/mL) and peaked 12 hours after closure (4.7μg/mL; standard deviation [SD], 3.2). Wound concentrations were 922 μg/mL (SD, 523) 3 hours after closure and 207 μg/mL (SD, 317) at 24 hours. VP had a half-life of 7.2 hours (95% confidence interval, 7.0-9.3) in TJA wounds. VP produced highly therapeutic intrawound concentrations while yielding low systemic levels in TJA. VP may serve as a safe adjunct in the prevention of periprosthetic joint infection. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Spacesuit mobility joints

    NASA Technical Reports Server (NTRS)

    Vykukal, H. C. (Inventor)

    1978-01-01

    Joints for use in interconnecting adjacent segments of an hermetically sealed spacesuit which have low torques, low leakage and a high degree of reliability are described. Each of the joints is a special purpose joint characterized by substantially constant volume and low torque characteristics. Linkages which restrain the joint from longitudinal distension and a flexible, substantially impermeable diaphragm of tubular configuration spanning the distance between pivotally supported annuli are featured. The diaphragms of selected joints include rolling convolutions for balancing the joints, while various joints include wedge-shaped sections which enhance the range of motion for the joints.

  3. Computer guided restoration of joint line and femoral offset in cruciate substituting total knee arthroplasty.

    PubMed

    Shetty, Gautam M; Mullaji, Arun; Bhayde, Sagar

    2012-10-01

    This prospective study aimed to evaluate radiographically, change in joint line and femoral condylar offset with the optimized gap balancing technique in computer-assisted, primary, cruciate-substituting total knee arthroplasties (TKAs). One hundred and twenty-nine consecutive computer-assisted TKAs were evaluated radiographically using pre- and postoperative full-length standing hip-to-ankle, antero-posterior and lateral radiographs to assess change in knee deformity, joint line height and posterior condylar offset. In 49% of knees, there was a net decrease (mean 2.2mm, range 0.2-8.4mm) in joint line height postoperatively whereas 46.5% of knees had a net increase in joint line height (mean 2.5mm, range 0.2-11.2mm). In 93% of the knees, joint line was restored to within ± 5 mm of preoperative values. In 53% of knees, there was a net increase (mean 2.9 mm, range 0.2-12 mm) in posterior offset postoperatively whereas 40% of knees had a net decrease in posterior offset (mean 4.2mm, range 0.6-20mm). In 82% of knees, the posterior offset was restored within ± 5 mm of preoperative values. Based on radiographic evaluation in extension and at 30° flexion, the current study clearly demonstrates that joint line and posterior femoral condylar offset can be restored in the majority of computer-assisted, cruciate-substituting TKAs to within 5mm of their preoperative value. The optimized gap balancing feature of the computer software allows the surgeon to simulate the effect of simultaneously adjusting femoral component size, position and distal femoral resection level on joint line and posterior femoral offset. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Total joint Perioperative Surgical Home: an observational financial review.

    PubMed

    Raphael, Darren R; Cannesson, Maxime; Schwarzkopf, Ran; Garson, Leslie M; Vakharia, Shermeen B; Gupta, Ranjan; Kain, Zeev N

    2014-01-01

    The numbers of people requiring total arthroplasty is expected to increase substantially over the next two decades. However, increasing costs and new payment models in the USA have created a sustainability gap. Ad hoc interventions have reported marginal cost reduction, but it has become clear that sustainability lies only in complete restructuring of care delivery. The Perioperative Surgical Home (PSH) model, a patient-centered and physician-led multidisciplinary system of coordinated care, was implemented at UC Irvine Health in 2012 for patients undergoing primary elective total knee arthroplasty (TKA) or total hip arthroplasty (THA). This observational study examines the costs associated with this initiative. The direct cost of materials and services (excluding professional fees and implants) for a random index sample following the Total Joint-PSH pathway was used to calculate per diem cost. Cost of orthopedic implants was calculated based on audit-verified direct cost data. Operating room and post-anesthesia care unit time-based costs were calculated for each case and analyzed for variation. Benchmark cost data were obtained from literature search. Data are presented as mean ± SD (coefficient of variation) where possible. Total per diem cost was $10,042 ± 1,305 (13%) for TKA and $9,952 ± 1,294 (13%) for THA. Literature-reported benchmark per diem cost was $17,588 for TKA and $16,267 for THA. Implant cost was $7,482 ± 4,050 (54%) for TKA and $9869 ± 1,549 (16%) for THA. Total hospital cost was $17,894 ± 4,270 (24%) for TKA and $20,281 ± 2,057 (10%) for THA. In-room to incision time cost was $1,263 ± 100 (8%) for TKA and $1,341 ± 145 (11%) for THA. Surgery time cost was $1,558 ± 290 (19%) for TKA and $1,930 ± 374 (19%) for THA. Post-anesthesia care unit time cost was $507 ± 187 (36%) for TKA and $557 ± 302 (54%) for THA. Direct hospital costs were driven substantially below USA benchmark levels using the Total Joint-PSH pathway. The incremental

  5. Arch structure is associated with unique joint work, relative joint contributions and stiffness during landing.

    PubMed

    Powell, Douglas W; Queen, Robin M; Williams, D S Blaise

    2016-10-01

    To examine lower extremity joint contributions to a landing task in high-(HA) and low-arched (LA) female athletes by quantifying vertical stiffness, joint work and relative joint contributions to landing. Twenty healthy female recreational athletes (10 HA and 10 LA) performed five barefoot drop landings from a height of 30cm. Three-dimensional kinematics (240Hz) and ground reaction forces (960Hz) were recorded simultaneously. Vertical stiffness, joint work values and relative joint work values were calculated using Visual 3D and MatLab. HA athletes had significantly greater vertical stiffness compared to LA athletes (p=0.013). Though no differences in ankle joint work were observed (p=0.252), HA athletes had smaller magnitudes of knee (p=0.046), hip (p=0.019) and total lower extremity joint work values (p=0.016) compared to LA athletes. HA athletes had greater relative contributions of the ankle (p=0.032) and smaller relative contributions of the hip (p=0.049) compared to LA athletes. No differences in relative contributions of the knee were observed (p=0.255). These findings demonstrate that aberrant foot structure is associated with unique contributions of lower extremity joints to load attenuation during landing. These data may provide insight into the unique injury mechanisms associated with arch height in female athletes. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. On the stiffness matrix of the intervertebral joint: application to total disk replacement.

    PubMed

    O'Reilly, Oliver M; Metzger, Melodie F; Buckley, Jenni M; Moody, David A; Lotz, Jeffrey C

    2009-08-01

    The traditional method of establishing the stiffness matrix associated with an intervertebral joint is valid only for infinitesimal rotations, whereas the rotations featured in spinal motion are often finite. In the present paper, a new formulation of this stiffness matrix is presented, which is valid for finite rotations. This formulation uses Euler angles to parametrize the rotation, an associated basis, which is known as the dual Euler basis, to describe the moments, and it enables a characterization of the nonconservative nature of the joint caused by energy loss in the poroviscoelastic disk and ligamentous support structure. As an application of the formulation, the stiffness matrix of a motion segment is experimentally determined for the case of an intact intervertebral disk and compared with the matrices associated with the same segment after the insertion of a total disk replacement system. In this manner, the matrix is used to quantify the changes in the intervertebral kinetics associated with total disk replacements. As a result, this paper presents the first such characterization of the kinetics of a total disk replacement.

  7. Human knee joint anatomy revisited: morphometry in the light of sex-specific total knee arthroplasty.

    PubMed

    Dargel, Jens; Michael, Joern W P; Feiser, Janna; Ivo, Roland; Koebke, Juergen

    2011-04-01

    This study investigates differences in the anatomy of male and female knee joints to contribute to the current debate on sex-specific total knee implants. Morphometric data were obtained from 60 human cadaver knees, and sex differences were calculated. All data were corrected for height, and male and female specimens presenting with an identical length of the femur were analyzed as matched pairs. Male linear knee joint dimensions were significantly larger when compared with females. When corrected for differences in height, medial-lateral dimensions of male knees were significantly larger than female; however, matched paired analysis did not prove these differences to be consistent. Although implant design should focus interindividual variations in knee joint anatomy, our data do not support the concept of a female-specific implant design. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Medicaid payer status is associated with in-hospital morbidity and resource utilization following primary total joint arthroplasty.

    PubMed

    Browne, James A; Novicoff, Wendy M; D'Apuzzo, Michele R

    2014-11-05

    Previous reports suggest that there are major disparities in outcomes following total joint arthroplasty among patients with different payer statuses. The explanation for these differences is largely unknown and may result from confounding variables. The Affordable Care Act expansion of Medicaid coverage in 2014 makes the examination of these disparities particularly relevant. The Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample (NIS) database was used to identify patients who had undergone primary hip or knee arthroplasty from 2002 through 2011. Complications, costs, and length of hospital stay for patients with Medicaid were compared with those for non-Medicaid patients. Each Medicaid patient was matched to a non-Medicaid patient according to age, sex, race, type of total joint arthroplasty, procedure year, hospital characteristics, smoking status, and all twenty-nine comorbidities defined in the NIS-modified Elixhauser comorbidity measure. It was determined that 191,911 patients who underwent total joint arthroplasty had Medicaid payer status (2.8% of the entire total joint arthroplasty population), and 107,335 (56%) of these Medicaid patients were matched one to one to a non-Medicaid patient for all variables for the adjusted analysis. After matching, Medicaid patients were found to have a higher prevalence of postoperative in-hospital infection (odds ratio [OR], 1.7; 95% confidence interval [CI], 1.3 to 2.1), wound dehiscence (OR, 2.2; 95% CI, 1.4 to 3.4), and hematoma or seroma (OR, 1.3; 95% CI, 1.2 to 1.4) but a lower risk of cardiac complications (OR, 0.7; CI, 0.6 to 0.9). The length of the hospital stay was longer, total cost was higher, and discharge to an inpatient facility was more frequent for patients with Medicaid status (p < 0.01). Compared with non-Medicaid patients, Medicaid patients have a significantly higher risk for certain postoperative in-hospital complications and consume more resources following total joint

  9. Periprosthetic joint infection: are patients with multiple prosthetic joints at risk?

    PubMed

    Jafari, S Mehdi; Casper, David S; Restrepo, Camilo; Zmistowski, Benjamin; Parvizi, Javad; Sharkey, Peter F

    2012-06-01

    Patients who present with a periprosthetic joint infection in a single joint may have multiple prosthetic joints. The risk of these patients developing a subsequent infection in another prosthetic joint is unknown. Our purposes were (1) to identify the risk of developing a subsequent infection in another prosthetic joint and (2) to describe the time span and organism profile to the second prosthetic infection. We retrospectively identified 55 patients with periprosthetic joint infection who had another prosthetic joint in place at the time of presentation. Of the 55 patients, 11 (20%) developed a periprosthetic joint infection in a second joint. The type of organism was the same as the first infection in 4 (36%) of 11 patients. The time to developing a second infection averaged 2.0 years (range, 0-6.9 years). Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Superior Recess Access of the Lumbar Facet Joint.

    PubMed

    Demir-Deviren, Sibel; Singh, Sukhminder; Hanelin, Joshua

    2017-04-01

    Descriptive approach to accessing the lumbar facet joint by superior recess. This study is aimed to describe an approach to accessing the lumbar facet joint through targeting the superior recess during lumbar facet joint injections. Lumbar facet joint injections are routinely performed for both the diagnosis and treatment of chronic low back pain. Previous studies either did not specify which part of the joint to target, or recommended targeting the inferior aspect of the joint to access the inferior recess. One study did mention the superior recess as an alternative to injecting the inferior recess, but none has focused on description of the technique. This is the first time this technique has been described. The records and fluoroscopic images were reviewed for all patients over a period of 9 months (January-September 2012) using the proposed technique. This resulted in a total of 48 patients; 15 men, 29 women, and a total of 117 facet joint intra-articular injections. Among these 48 patients, injections were repeated in total of 4 cases. The average time of injections among 4 repeat cases was 121 days. The success of the procedure was confirmed with an arthrogram demonstrating contrast flowing from the superior recess inferiorly through the joint space. Successful access of the lumbar facet joint through puncture of the superior recess was seen in 114 cases, with 3 unsuccessful attempts to enter facet joints due to osteophytes at involved levels. There were no complications observed during the procedure. We find this approach to be highly successful, safe, and well tolerated by the patient and recommend it as a technique for access of the lumbar facet joint in those patients in whom direct puncture of the inferior recess is difficult.

  11. The Effect of Advancing Age on Total Joint Replacement Outcomes

    PubMed Central

    Noiseux, Nicolas; Linson, Eric; Cram, Peter

    2015-01-01

    Objective: To describe age-related differences in outcomes among older adults undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA). Design: Retrospective study. Participants: A total of 1792 patients who underwent primary THA or TKA at the University of Iowa Hospitals and Clinics between 2010 and 2013 were identified in the University HealthSystem Consortium Database and University of Iowa Orthopedics Joint Replacement Registry. Main Outcome Measures: Hospital length of stay (LOS), 30-day readmission rate, in-hospital mortality, number of days admitted to intensive care unit (ICU discharge disposition), in-hospital complications (pulmonary embolism, deep vein thrombosis, wound infection, hemorrhage, sepsis, or myocardial infarction), quality of life (measured using Short-Form 36 [SF-36]), discharge disposition (home, home with home health, nursing home, inpatient rehabilitation, transfer to another acute care hospital, and dead), and total patient level observed hospital cost (based on hospital charge information from each revenue code and estimated labor costs). Outcomes were compared in patients stratified by age and categorized by decade (ie, ≤50, 51-60, 61-70, 71-80, and ≥81). Results: A total of 871 THAs and 921 TKAs were performed. The mean age of our cohort was 60.5 years and 56.1% were women. In-hospital complication rates and ICU utilization progressively increased with increasing age. There was also a higher likelihood of skilled nursing facility placement and longer LOS. There was no increase in 30-day readmissions, mortality, or total cost. Improvements in patient reported outcomes (SF-36) scores were similar for all age-groups. Conclusions: Compared to younger patients, older THA and TKA recipients were more likely to experience postoperative complications, admission to the ICU, discharge to a skilled care facility, and had longer hospital LOS. Improvements in patient-related outcomes were similar across all age-groups. These

  12. Knee joint mobilization reduces secondary mechanical hyperalgesia induced by capsaicin injection into the ankle joint.

    PubMed

    Sluka, K A; Wright, A

    2001-01-01

    Joint mobilization is a treatment approach commonly used by physical therapists for the management of a variety of painful conditions. However, the clinical effectiveness when compared to placebo and the neurophysiological mechanism of action are not known. The purpose of this study was to establish that application of a manual therapy technique will produce antihyperalgesia in an animal model of joint inflammation and that the antihyperalgesia produced by joint mobilization depends on the time of treatment application. Capsaicin (0.2%, 50 microl) was injected into the lateral aspect of the left ankle joint and mechanical withdrawal threshold assessed before and after capsaicin injection in Sprague-Dawley rats. Joint mobilization of the ipsilateral knee joint was performed 2 h after capsaicin injection for a total of 3 min, 9 min or 15 min under halothane anaesthesia. Control groups included animals that received halothane for the same time as the group that received joint mobilization and those whose limbs were held for the same duration as the mobilization (no halothane). Capsaicin resulted in a decreased mechanical withdrawal threshold by 2 h after injection that was maintained through 4 h. Both 9 and 15 min of mobilization, but not 3 min of mobilization, increased the withdrawal threshold to mechanical stimuli to baseline values when compared with control groups. The antihyperalgesic effect of joint mobilization lasted 30 min. Thus, joint mobilization (9 or 15 min duration) produces a significant reversal of secondary mechanical hyperalgesia induced by intra-articular injection of capsaicin. Copyright 2001 European Federation of Chapters of the International Association for the Study of Pain.

  13. Hereditary hemochromatosis as a risk factor for joint replacement surgery.

    PubMed

    Sahinbegovic, Enijad; Dallos, Tomás; Aigner, Elmar; Axmann, Roland; Engelbrecht, Matthias; Schöniger-Hekele, Maximilian; Karonitsch, Thomas; Farkas, Martin; Karger, Thomas; Willeit, Johann; Stölzel, Ulrich; Keysser, Gernot; Datz, Christian; Kiechl, Stefan; Schett, Georg; Zwerina, Jochen

    2010-07-01

    Hemochromatosis is an inherited disease with iron overload and joint involvement resembling osteoarthritis. To determine the rate of joint replacement surgery in patients with hemochromatosis, we performed a cross-sectional cohort study. A total of 199 individuals with hereditary hemochromatosis were included. The prevalence of joint replacement surgery in hip, knee, and ankle joints because of secondary osteoarthritis was assessed. Data were compared with 917 healthy subjects from the population-based Bruneck study. A total of 32 of 199 individuals with hemochromatosis received joint replacement surgery with a total number of 52 joints replaced. Compared with expected rates in healthy individuals, patients with hemochromatosis had a significantly higher risk for joint replacement surgery (odds ratio 9.0; confidence interval, 4.6-17.4). Joint replacement occurred significantly earlier in life in patients with hemochromatosis; 21.9% of the patients with hemochromatosis and 1.7% of healthy individuals required joint replacement before the age of 50 years (P=.0027). Moreover, patients with hemochromatosis were more likely to require multiple joint replacements (8.5%) than the control group (expected rate 0.3%; P=.0001). Hemochromatosis is a risk factor for joint replacement surgery because of severe secondary osteoarthritis. Copyright 2010 Elsevier Inc. All rights reserved.

  14. Reducing Length of Stay in Total Joint Arthroplasty Care.

    PubMed

    Walters, Megan; Chambers, Monique C; Sayeed, Zain; Anoushiravani, Afshin A; El-Othmani, Mouhanad M; Saleh, Khaled J

    2016-10-01

    As health care reforms continue to improve quality of care, significant emphasis will be placed on evaluation of orthopedic patient outcomes. Total joint arthroplasty (TJA) has a proven track record of enhancing patient quality of life and are easily replicable. The outcomes of these procedures serve as a measure of health care initiative success. Specifically, length of stay, will be targeted as a marker of quality of surgical care delivered to TJA patients. Within this review, we will discuss preoperative and postoperative methods by which orthopedic surgeons may enhance TJA outcomes and effectively reduce length of stay. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Episode of Care Payments in Total Joint Arthroplasty and Cost Minimization Strategies.

    PubMed

    Nwachukwu, Benedict U; O'Donnell, Evan; McLawhorn, Alexander S; Cross, Michael B

    2016-02-01

    Total joint arthroplasty (TJA) is receiving significant attention in the US health care system for cost containment strategies. Specifically, payer organizations have embraced and are implementing bundled payment schemes in TJA. Consequently, hospitals and providers involved in the TJA care cycle have sought to adapt to the new financial pressures imposed by episode of care payment models by analyzing what components of the total "event" of a TJA are most essential to achieve a good outcome after TJA. As part of this review, we analyze and discuss a health economic study by Snow et al. As part of their study, the authors aimed to understand the association between preoperative physical therapy (PT) and post-acute care resource utilization, and its effect on the total cost of care during total joint arthroplasty. The purpose of this current review therefore is to (1) describe and analyze the findings presented by Snow et al. and (2) provide a framework for analyzing and critiquing economic analyses in orthopedic surgery. The study under review, while having important strengths, has several notable limitations that are important to keep in mind when making policy and coverage decisions. We support cautious interpretation and application of study results, and we encourage maintained attention to economic analysis in orthopedics as well as continued care path redesign to maximize value for patients and health care providers.

  16. Impact extractive fracture of jointed steel plates of a bolted joint

    NASA Astrophysics Data System (ADS)

    Daimaruya, M.; Fujiki, H.; Ambarita, H.

    2012-08-01

    This study is concerned with the development of a fracture criterion for the impact fracture of jointed steel plates of a bolted joint used in a car body. For the accurate prediction of crash characteristics of car bodies by computer-aided engineering (CAE), it is also necessary to examine the behavior and fracture of jointed steel plates subjected to impact loads. Although the actual impact fracture of jointed steel plates of a bolted joint used in cars is complicated, for simplifying the problem it might be classified into the shear fracture and the extractive fracture of jointed steel plates. Attention is given to the extractive fracture of jointed steel plates in this study. The extractive behavior and fracture of three kinds of steel plates used for cars are examined in experiments and numerical simulations. The impact extraction test of steel plates jointed by a bolt is performed using the one-bar method, together with the static test. In order to understand the mechanism of extractive fracture process of jointed steel plates, numerical simulations by a FEM code LS-DYNA are also carried out. The obtained results suggest that a stress-based fracture criterion may be developed for the impact extractive fracture of jointed steel plates of a bolted joint used in a car body.

  17. Astym® Therapy for the Management of Recalcitrant Knee Joint Stiffness after Total Knee Arthroplasty.

    PubMed

    Bhave, Anil; Corcoran, James; Cherian, Jeffery J; Mont, Michael A

    2016-01-01

    Knee stiffness is a common complication after total knee arthroplasty (TKA). Despite studies published on the surgical management of reduced range of motion (ROM) after TKA, there is limited evidence on the nonoperative management of joint and soft tissue imbalances possibly contributing to reduced knee ROM. This report assesses changes in ROM, pain, function, and patellar tendon length after Astym® joint mobilization use. A 38-year-old male professional skier had a right TKA 3 months before presentation with 2 subsequent manipulations under anesthesia secondary to persistent knee stiffness. He had patellar baja on radiograph, a reduced arc of ROM, reduced patellar mobility and muscular extensibility, and pain to palpation along the patellar tendon. He had 12 visits of physical therapy with the use of Astym®, patellar mobilization, and tibio-femoral mobilizations with movement. The patient also used a customized knee device at home for prolonged knee extension stretching. The patient was treated for 12 visits, along with home use of customized bracing for knee extension. Significant improvements were seen in pain, function, and ROM. He returned to work full-time, ambulated prolonged distances, and negotiated stairs pain-free. He also demonstrated resolution of patellar baja radiographically. Conservative management of recalcitrant knee joint stiffness after primary TKA can be effective in restoring knee mobility and reducing pain and activity limitation. A multimodal approach using Astym® treatment, customized knee bracing, and targeted joint mobilization can be effective in resolving knee joint stiffness.

  18. Clinical synovitis in a particular joint is associated with progression of erosions and joint space narrowing in that same joint, but not in patients initially treated with infliximab.

    PubMed

    Klarenbeek, N B; Güler-Yüksel, M; van der Heijde, D M F M; Hulsmans, H M J; Kerstens, P J S M; Molenaar, T H E; de Sonnaville, P B J; Huizinga, T W J; Dijkmans, B A C; Allaart, C F

    2010-12-01

    To assess the relationship between joint tenderness, swelling and joint damage progression in individual joints and to evaluate the influence of treatment on these relationships. First-year data of the Behandel Strategieën (BeSt) study were used, in which patients recently diagnosed as having rheumatoid arthritis (RA) were randomly assigned into four different treatment strategies. Baseline and 1-year x-rays of the hands and feet were assessed using the Sharp-van der Heijde score (SHS). With generalised estimating equations, 3-monthly assessments of tender and swollen joints of year 1 were related to erosion progression, joint space narrowing (JSN) progression and total SHS progression at the individual joint level (definition > 0.5 SHS units) in year 1, corrected for potential confounders and within-patient correlation for multiple joints per patient. During year 1, 59% of all 13 959 joints analysed were ever tender and 45% ever swollen, 2.1% showed erosion progression, 1.9% JSN progression and 3.6% SHS progression. Swelling and tenderness were both independently associated with erosion and JSN progression with comparable OR, although with higher OR in the hands than in the feet. Local swelling and tenderness were not associated with local damage progression in patients initially treated with infliximab. Clinical signs of synovitis are associated with erosion and JSN progression in individual joints after 1 year in RA. A disconnect between synovitis and joint damage progression was observed at joint level in patients who were treated with methotrexate and infliximab as initial treatment, confirming the disconnect between synovitis and the development of joint damage in tumour necrosis factor blockers seen at patient level.

  19. Joint Instability and Osteoarthritis

    PubMed Central

    Blalock, Darryl; Miller, Andrew; Tilley, Michael; Wang, Jinxi

    2015-01-01

    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. PMID:25741184

  20. Joint instability and osteoarthritis.

    PubMed

    Blalock, Darryl; Miller, Andrew; Tilley, Michael; Wang, Jinxi

    2015-01-01

    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.

  1. MR safety and compatibility of a noninvasively expandable total-joint endoprosthesis.

    PubMed

    Ogg, Robert J; McDaniel, C Brian; Wallace, Donald; Pitot, Pierre; Neel, Michael D; Kaste, Sue C

    2005-09-01

    A noninvasively expandable total-joint endoprosthesis is now available for pediatric patients; the prosthesis can be lengthened by external application of a magnetic field. We investigated the risks of unintentional heating or lengthening of the prosthesis during MR imaging and evaluated the effect of the device on the diagnostic efficacy of MR imaging of surrounding tissues. We performed MR imaging at 1.5 T by using standard pulse sequences and pulse sequences with high-gradient and high-radiofrequency duty cycle. MR imaging caused no measurable change in prosthesis length, and the temperature of the prosthesis increased by less than 1 degrees C during repeated 14-min exposures. Despite significant signal loss and image distortion around the prosthetic joint, clinically useful images were obtained as close as 12 cm from the ends of the prosthetic stems, measured toward the body of the device. Thus, the prosthesis can be safely exposed to MR imaging pulse sequences at 1.5 T, and the visualization of some tissue surrounding the device is clinically useful.

  2. Endoglin (CD105) expression differentiates between aseptic loosening and periprosthetic joint infection after total joint arthroplasty.

    PubMed

    Jansen, Philipp; Mumme, Torsten; Randau, Thomas; Gravius, Sascha; Hermanns-Sachweh, Benita

    2014-01-01

    The differentiation between aseptic loosening and periprosthetic joint infection (PJI) after total joint arthroplasty is essential for successful therapy. A better understanding of pathogenesis of aseptic loosening and PJI may help to prevent or treat these complications. Previous investigations revealed an increased vascularization in the periprosthetic membrane in cases of PJI via PET signals. Based on these findings our hypothesis was that PJI is associated with an increased neovascularization in the periprosthetic membrane. Tissue samples from periprosthetic membranes of the bone-implant interface were investigated histologically for inflammation, wear particles, vascularization and fibrosis. To identify vascular structures antibodies against CD 31, CD 34, factor VIII and CD 105 (endoglin) were applied for immunohistochemical investigations. According to a consensus classification of Morawietz the tissue samples were divided into four types: type I (wear particle induced type, n = 11), type II (infectious type, n = 7), type III (combined type, n = 7) and type IV (indeterminate type, n = 7). Patients with PJI (type II) showed a pronounced infiltration of neutrophil granulocytes in the periprosthetic membrane and an enhanced neovascularization indicated by positive immunoreaction with antibodies against CD 105 (endoglin). Tissue samples classified as type I, type III and type IV showed significantly less immune reaction for CD 105. In cases of aseptic loosening and PJI vascularization is found in different expression in periprosthetic membranes. However, in aseptic loosening, there is nearly no neovascularization with CD 105-positive immune reaction. Therefore, endoglin (CD 105) expression allows for differentiation between aseptic loosening and PJI.

  3. Total joint Perioperative Surgical Home: an observational financial review

    PubMed Central

    2014-01-01

    Background The numbers of people requiring total arthroplasty is expected to increase substantially over the next two decades. However, increasing costs and new payment models in the USA have created a sustainability gap. Ad hoc interventions have reported marginal cost reduction, but it has become clear that sustainability lies only in complete restructuring of care delivery. The Perioperative Surgical Home (PSH) model, a patient-centered and physician-led multidisciplinary system of coordinated care, was implemented at UC Irvine Health in 2012 for patients undergoing primary elective total knee arthroplasty (TKA) or total hip arthroplasty (THA). This observational study examines the costs associated with this initiative. Methods The direct cost of materials and services (excluding professional fees and implants) for a random index sample following the Total Joint-PSH pathway was used to calculate per diem cost. Cost of orthopedic implants was calculated based on audit-verified direct cost data. Operating room and post-anesthesia care unit time-based costs were calculated for each case and analyzed for variation. Benchmark cost data were obtained from literature search. Data are presented as mean ± SD (coefficient of variation) where possible. Results Total per diem cost was $10,042 ± 1,305 (13%) for TKA and $9,952 ± 1,294 (13%) for THA. Literature-reported benchmark per diem cost was $17,588 for TKA and $16,267 for THA. Implant cost was $7,482 ± 4,050 (54%) for TKA and $9869 ± 1,549 (16%) for THA. Total hospital cost was $17,894 ± 4,270 (24%) for TKA and $20,281 ± 2,057 (10%) for THA. In-room to incision time cost was $1,263 ± 100 (8%) for TKA and $1,341 ± 145 (11%) for THA. Surgery time cost was $1,558 ± 290 (19%) for TKA and $1,930 ± 374 (19%) for THA. Post-anesthesia care unit time cost was $507 ± 187 (36%) for TKA and $557 ± 302 (54%) for THA. Conclusions Direct hospital costs were driven substantially below USA benchmark levels using the Total

  4. Joint Stability in Total Knee Arthroplasty: What Is the Target for a Stable Knee?

    PubMed

    Wright, Timothy M

    2017-02-01

    Instability remains a common cause of failure in total knee arthroplasty. Although approaches for surgical treatment of instability exist, the target for initial stability remains elusive, increasing the likelihood that failures will persist because adequate stability is not restored when performing the primary arthroplasty. Although the mechanisms that stabilize the knee joint-contact between the articular surfaces, ligamentous constraints, and muscle forces-are well-defined, their relative importance and the interplay among them throughout functions of daily living are poorly understood. The problem is exacerbated by the complex multiplanar motions that occur across the joint and the large variations in these motions across the population, suggesting that stability targets may need to be patient-specific.

  5. Performance characteristics of broth-only cultures after revision total joint arthroplasty.

    PubMed

    Smith, Eric B; Cai, Jenny; Wynne, Rachael; Maltenfort, Mitchell; Good, Robert P

    2014-11-01

    Surgeons frequently obtain intraoperative cultures at the time of revision total joint arthroplasty. The use of broth or liquid medium before applying the sample to the agar medium may be associated with contamination and false-positive cultures; however, the degree to which this is the case is not known. We (1) calculated the performance characteristics of broth-only cultures (sensitivity, specificity, positive predictive value, and negative predictive value) and (2) characterized the organisms identified in broth to determine whether a specific organism showed increased proclivity for true-positive periprosthetic joint infection (PJI). A single-institution retrospective chart review was performed on 257 revision total joint arthroplasties from 2009 through 2010. One hundred ninety (74%) had cultures for review. All culture results, as well as treatment, if any, were documented and patients were followed for a minimum of 1 year for evidence of PJI. Cultures were measured as either positive from the broth only or broth negative. The true diagnosis of infection was determined by the Musculoskeletal Infection Society criteria during the preoperative workup or postoperatively at 1 year for purposes of calculating the performance characteristics of the broth-only culture. The sensitivity, specificity, positive predictive value, and negative predictive value were 19%, 88%, 13%, and 92%, respectively. The most common organism identified was coagulase-negative Staphylococcus (16 of 24 cases, 67%). Coagulase-negative Staphylococcus was present in all three true-positive cases; however, it was also found in 13 of the false-positive cases. The broth-only positive cultures showed poor sensitivity and positive predictive value but good specificity and negative predictive value. The good specificity indicates that it can help to rule in the presence of PJI; however, the poor sensitivity makes broth-only culture an unreliable screening test. We recommend that broth

  6. The hindlimb in walking horses: 2. Net joint moments and joint powers.

    PubMed

    Clayton, H M; Hodson, E; Lanovaz, J L; Colborne, G R

    2001-01-01

    The objective of the study was to describe net joint moments and joint powers in the equine hindlimb during walking. The subjects were 5 sound horses. Kinematic and force data were collected synchronously and combined with morphometric information to determine net joint moments at each hindlimb joint throughout stance and swing. The results showed that the net joint moment was on the caudal/plantar side of all hindlimb joints at the start of stance when the limb was being actively retracted. It moved to the cranial/dorsal side around 24% stride at the hip and stifle and in terminal stance at the more distal joints. It remained on the cranial/dorsal side of all joints during the first half of swing to provide active limb protraction, then moved to the caudal/plantar aspect to reverse the direction of limb motion prior to ground contact. The hip joint was the main source of energy generation throughout the stride. It was assisted by the tarsal joint in both stance and swing phases and by the fetlock joint during the stance phase. The coffin joint acted as an energy damper during stance, whereas the stifle joint absorbed almost equal amounts of energy in the stance and swing phases. The coffin and fetlock joints absorbed energy as the limb was protracted and retracted during the swing phase, suggesting that their movements were driven by inertial forces. Future studies will apply these findings to detect changes in the energy profiles due to specific soft tissue injuries.

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

    PubMed Central

    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 femoral bone mineral density after patellofemoral joint replacement. It is unclear whether this is due to periprosthetic stress shielding. The main objective of the current study was to evaluate the stress shielding effect of prosthetic replacement with 2 different patellofemoral prosthetic designs and with a total knee prosthesis. Methods We developed a finite element model of an intact patellofemoral joint, and finite element models of patellofemoral joint replacement with a Journey PFJ prosthesis, a Richards II prosthesis, and a Genesis II total knee prosthesis. For each of these 4 finite element models, the average Von Mises stress in 2 clinically relevant regions of interest were evaluated during a simulated squatting movement until 120 degrees of flexion. Results During deep knee flexion, in the anterior region of interest, the average Von Mises stress with the Journey PFJ design was comparable to the physiological knee, while reduced by almost 25% for both the Richards II design and the Genesis II total knee joint replacement design. The average Von Mises stress in the supracondylar region of interest was similar for both patellofemoral prosthetic designs and the physiological model, with slightly lower stress for the Genesis II design. Conclusions Patellofemoral joint replacement results in periprosthetic stress-shielding, although to a smaller degree than in total knee replacement. Specific patellofemoral prosthetic design properties may result in differences in femoral stress shielding. PMID:22704638

  8. Cost-Effective Mobile-Based Healthcare System for Managing Total Joint Arthroplasty Follow-Up.

    PubMed

    Bitsaki, Marina; Koutras, George; Heep, Hansjoerg; Koutras, Christos

    2017-01-01

    Long-term follow-up care after total joint arthroplasty is essential to evaluate hip and knee arthroplasty outcomes, to provide information to physicians and improve arthroplasty performance, and to improve patients' health condition. In this paper, we aim to improve the communication between arthroplasty patients and physicians and to reduce the cost of follow-up controls based on mobile application technologies and cloud computing. We propose a mobile-based healthcare system that provides cost-effective follow-up controls for primary arthroplasty patients through questions about symptoms in the replaced joint, questionnaires (WOMAC and SF-36v2) and the radiological examination of knee or hip joint. We also perform a cost analysis for a set of 423 patients that were treated in the University Clinic for Orthopedics in Essen-Werden. The estimation of healthcare costs shows significant cost savings (a reduction of 63.67% for readmission rate 5%) in both the University Clinic for Orthopedics in Essen-Werden and the state of North Rhine-Westphalia when the mobile-based healthcare system is applied. We propose a mHealth system to reduce the cost of follow-up assessments of arthroplasty patients through evaluation of diagnosis, self-monitoring, and regular review of their health status.

  9. The Analysis of Adhesively Bonded Advanced Composite Joints Using Joint Finite Elements

    NASA Technical Reports Server (NTRS)

    Stapleton, Scott E.; Waas, Anthony M.

    2012-01-01

    The design and sizing of adhesively bonded joints has always been a major bottleneck in the design of composite vehicles. Dense finite element (FE) meshes are required to capture the full behavior of a joint numerically, but these dense meshes are impractical in vehicle-scale models where a course mesh is more desirable to make quick assessments and comparisons of different joint geometries. Analytical models are often helpful in sizing, but difficulties arise in coupling these models with full-vehicle FE models. Therefore, a joint FE was created which can be used within structural FE models to make quick assessments of bonded composite joints. The shape functions of the joint FE were found by solving the governing equations for a structural model for a joint. By analytically determining the shape functions of the joint FE, the complex joint behavior can be captured with very few elements. This joint FE was modified and used to consider adhesives with functionally graded material properties to reduce the peel stress concentrations located near adherend discontinuities. Several practical concerns impede the actual use of such adhesives. These include increased manufacturing complications, alterations to the grading due to adhesive flow during manufacturing, and whether changing the loading conditions significantly impact the effectiveness of the grading. An analytical study is conducted to address these three concerns. Furthermore, proof-of-concept testing is conducted to show the potential advantages of functionally graded adhesives. In this study, grading is achieved by strategically placing glass beads within the adhesive layer at different densities along the joint. Furthermore, the capability to model non-linear adhesive constitutive behavior with large rotations was developed, and progressive failure of the adhesive was modeled by re-meshing the joint as the adhesive fails. Results predicted using the joint FE was compared with experimental results for various

  10. Spacesuit mobility knee joints

    NASA Technical Reports Server (NTRS)

    Vykukal, H. C. (Inventor)

    1979-01-01

    Pressure suit mobility joints are for use in interconnecting adjacent segments of an hermetically sealed spacesuit in which low torques, low leakage and a high degree of reliability are required. Each of the joints is a special purpose joint characterized by substantially constant volume and low torque characteristics and includes linkages which restrain the joint from longitudinal distension and includes a flexible, substantially impermeable diaphragm of tubular configuration spanning the distance between pivotally supported annuli. The diaphragms of selected joints include rolling convolutions for balancing the joints, while various joints include wedge-shaped sections which enhance the range of motion for the joints.

  11. Joint Enabling Capabilities Command

    Science.gov Websites

    Executive Director Chief of Staff Joint Planning Support Element Joint Communications Support Element mission Joint Enabling Capabilities Command provides decisive joint communications, planning and public and responsive support for joint communications, planning and public affairs. Priorities * Deliver

  12. Joint hypermobility in patients with chondromalacia patellae.

    PubMed

    al-Rawi, Z; Nessan, A H

    1997-12-01

    The relationship between joint mobility and chondromalacia patellae was reported in a prospective study. A total of 115 patients with chondromalacia patellae were compared with 110 healthy individuals without chondromalacia patellae, matched for age and sex, who served as a control group. The degree of joint mobility was scored on a scale of 0-9. The number of individuals with hypermobile joints and the total mobility scores were significantly higher in patients with chondromalacia patellae when compared to the control group (P < 0.001). There were more hypermobile knees among knee joints with chondromalacia patellae when compared with the knees of the control group (P < 0.01). Chondromalacia patellae were bilateral in 57% of our patients. It occurred more frequently in the longer leg and was associated with quadriceps muscle wasting in 50% of patients. Flat feet and backache were reported significantly more often in patients compared with the control group (P < 0.05). It is concluded that hypermobility of the knee joint may be a contributing factor in the pathogenesis of chondromalacia patellae.

  13. MP Joint Arthritis

    MedlinePlus

    ... is extensive and severe, joint replacement or joint fusion are effective surgical options. Learn more about joint ... the tabs at the top (Video, Articles/WEB, Images, JHS, Products/Vendors), or the filters on the ...

  14. Predictors of Patient-Reported Outcomes of Total Joint Arthroplasty in a Developing Country.

    PubMed

    Bido, Jennifer; Yang, Ying H; Collins, Jamie E; Dong, Yan; Driscoll, Daniel A; Alcantara, Luis A; Thornhill, Thomas S; Katz, Jeffrey N

    2017-06-01

    In response to the growing burden of joint disease, developing countries are starting to create their own total joint arthroplasty (TJA) programs. To date, there has been limited research on predictors of TJA outcomes in a developing country. This investigation uses patient-reported outcome measures collected by a medical mission to assess predictors of TJA outcomes in the Dominican Republic. Baseline and postoperative information from 156 of the mission's recipients of hip and knee TJA was used. Demographics were abstracted from clinical notes, and self-reported pain and functional status were assessed using Western Ontario and McMaster University Osteoarthritis Index and Short-Form 36 measures. Bivariate analysis identified variables to include in multivariable regression models of factors associated with function and pain outcomes and improvement in these domains 1 or 2 years postoperatively. The cohort had a mean age of 61.3 years, 82% were female, 79% had total knee arthroplasty, and 42% of the procedures were bilateral. In multivariate analyses, at P < .05, male sex, better preoperative function, and use of bilateral procedure were associated with better functional outcome. Male sex and worse preoperative pain were associated with better pain outcome. Worse preoperative pain and function, as well as bilateral surgery were associated with greater improvement in function. Additionally, a greater number of bothersome joints was associated with greater pain reduction. Our findings of better follow-up pain scores among patients with worse pain preoperatively and better functional improvement among those undergoing bilateral replacements contrast with study results from developed countries. The explanations for these observations merit further study. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. In vivo six-degree-of-freedom knee-joint kinematics in overground and treadmill walking following total knee arthroplasty.

    PubMed

    Guan, Shanyuanye; Gray, Hans A; Schache, Anthony G; Feller, Julian; de Steiger, Richard; Pandy, Marcus G

    2017-08-01

    No data are available to describe six-degree-of-freedom (6-DOF) knee-joint kinematics for one complete cycle of overground walking following total knee arthroplasty (TKA). The aims of this study were firstly, to measure 6-DOF knee-joint kinematics and condylar motion for overground walking following TKA; and secondly, to determine whether such data differed between overground and treadmill gait when participants walked at the same speed during both tasks. A unique mobile biplane X-ray imaging system enabled accurate measurement of 6-DOF TKA knee kinematics during overground walking by simultaneously tracking and imaging the joint. The largest rotations occurred for flexion-extension and internal-external rotation whereas the largest translations were associated with joint distraction and anterior-posterior drawer. Strong associations were found between flexion-extension and adduction-abduction (R 2  = 0.92), joint distraction (R 2  = 1.00), and anterior-posterior translation (R 2  = 0.77), providing evidence of kinematic coupling in the TKA knee. Although the measured kinematic profiles for overground walking were grossly similar to those for treadmill walking, several statistically significant differences were observed between the two conditions with respect to temporo-spatial parameters, 6-DOF knee-joint kinematics, and condylar contact locations and sliding. Thus, caution is advised when making recommendations regarding knee implant performance based on treadmill-measured knee-joint kinematic data. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1634-1643, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  16. Joint sealant study

    DOT National Transportation Integrated Search

    1987-09-01

    ADOT has approximately 550 lane miles of jointed portland cement pavement under its jurisdiction. The current practice is to saw and seal the joints at the time of construction and reseal the joints under a rehabilitation project. ADOT does not speci...

  17. Revision for prosthetic joint infection following hip arthroplasty: Evidence from the National Joint Registry.

    PubMed

    Lenguerrand, E; Whitehouse, M R; Beswick, A D; Jones, S A; Porter, M L; Blom, A W

    2017-06-01

    We used the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man (NJR) to investigate the risk of revision due to prosthetic joint infection (PJI) for patients undergoing primary and revision hip arthroplasty, the changes in risk over time, and the overall burden created by PJI. We analysed revision total hip arthroplasties (THAs) performed due to a diagnosis of PJI and the linked index procedures recorded in the NJR between 2003 and 2014. The cohort analysed consisted of 623 253 index primary hip arthroplasties, 63 222 index revision hip arthroplasties and 7585 revision THAs performed due to a diagnosis of PJI. The prevalence, cumulative incidence functions and the burden of PJI (total procedures) were calculated. Overall linear trends were investigated with log-linear regression. We demonstrated a prevalence of revision THA due to prosthetic joint infection of 0.4/100 procedures following primary and 1.6/100 procedures following revision hip arthroplasty. The prevalence of revision due to PJI in the three months following primary hip arthroplasty has risen 2.3-fold (95% confidence interval (CI) 1.3 to 4.1) between 2005 and 2013, and 3.0-fold (95% CI 1.1 to 8.5) following revision hip arthroplasty. Over 1000 procedures are performed annually as a consequence of hip PJI, an increase of 2.6-fold between 2005 and 2013. Although the risk of revision due to PJI following hip arthroplasty is low, it is rising and, coupled with the established and further predicted increased incidence of both primary and revision hip arthroplasty, this represents a growing and substantial treatment burden. Cite this article : E. Lenguerrand, M. R. Whitehouse, A. D. Beswick, S. A. Jones, M. L. Porter, A. W. Blom. Revision for prosthetic joint infection following hip arthroplasty: Evidence from the National Joint Registry. Bone Joint Res 2017;6:391-398. DOI: 10.1302/2046-3758.66.BJR-2017-0003.R1. © 2017 Lenguerrand et al.

  18. Burden of Restraint, Disablement and Ethnic Identity: A Case Study of Total Joint Replacement for Osteoarthritis

    PubMed Central

    Harrison, Tracie

    2010-01-01

    Health disparities in total joint replacement have been documented based on gender and ethnicity in multiple countries. Absent are studies exploring the meaning of the procedures among diverse women, which is necessary to fully understand the impact of the disparity. Drawing on ethnographic data from a life course exploration of disablement among Mexican American women with mobility impairments, one woman’s reasons for forgoing a joint replacement are considered. It is suggested that inequalities in disablement cannot be understood without considering the mulitple cultural conflicts and loyalties that push and pull women in multiple directions. PMID:21767094

  19. Differences in knee joint kinematics and forces after posterior cruciate retaining and stabilized total knee arthroplasty.

    PubMed

    Wünschel, Markus; Leasure, Jeremi M; Dalheimer, Philipp; Kraft, Nicole; Wülker, Nikolaus; Müller, Otto

    2013-12-01

    Posterior cruciate ligament (PCL) retaining (CR) and -sacrificing (PS) total knee arthroplasties (TKA) are widely-used to treat osteoarthritis of the knee joint. The PS design substitutes the function of the PCL with a cam-spine mechanism which may produce adverse changes to joint kinematics and kinetics. CR- and PS-TKA were performed on 11 human knee specimens. Joint kinematics were measured with a dynamic knee simulator and motion tracking equipment. In-situ loads of the PCL and cam-spine were measured with a robotic force sensor system. Partial weight bearing flexions were simulated and external forces were applied. The PS-TKA rotated significantly less throughout the whole flexion range compared to the CR-TKA. Femoral roll back was greater in the PS-TKA; however, this was not correlated with lower quadriceps forces. Application of external loads produced significantly different in-situ force profiles between the TKA systems. Our data demonstrate that the PS-design significantly alters kinematics of the knee joint. Our data also suggest the cam-spine mechanism may have little influence on high flexion kinematics (such as femoral rollback) with most of the load burden shared by supporting implant and soft-tissue structures. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Conarticular congruence of the hominoid subtalar joint complex with implications for joint function in Plio-Pleistocene hominins.

    PubMed

    Prang, Thomas C

    2016-07-01

    The purpose of this study is to test the hypothesis that conarticular surfaces areas and curvatures are correlates of mobility at the hominoid talocalcaneal and talonavicular joints. Articular surface areas and curvatures of the talonavicular, anterior talocalcaneal, and posterior talocalcaneal joints were quantified using a total of 425 three-dimensional surface models of extant hominoid and fossil hominin tali, calcanei, and naviculars. Quadric surface fitting was used to calculate curvatures, pairwise comparisons were used to evaluate statistical differences between taxa, and regression was used to test for the effects of allometry. Pairwise comparisons show that the distributions of values for joint curvature indices follow the predicted arboreal-terrestrial morphocline in hominoid primates with no effect of body mass (PGLS p > 0.05). OH 8 (Homo habilis) and LB 1 (Homo floresiensis) can be accommodated within the range of human variation for the talonavicular joint, whereas MH2 (Australopithecus sediba) falls within the ranges of variation for Pan troglodytes and Gorilla gorilla in measures of posterior talocalcaneal joint congruity. Joint curvature indices are better discriminators than joint surface area indices, which may reflect a greater contribution of rotation, rather than translation, to joint movement in plantigrade taxa due to discrepancies in conarticular congruence and the "convex-concave" rule. The pattern of joint congruence in Au. sediba contributes to other data on the foot and ankle suggesting that the lateral side of the foot was more mobile than the medial side, which is consistent with suggestions of increased medial weight transfer associated with hyperpronation. Am J Phys Anthropol 160:446-457, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  1. Design and clinical outcome of a novel 3D-printed prosthetic joint replacement for the human temporomandibular joint.

    PubMed

    Ackland, David; Robinson, Dale; Lee, Peter Vee Sin; Dimitroulis, George

    2018-05-11

    Stock prosthetic temporomandibular joint replacements come in limited sizes, and do not always encompass the joint anatomy that presents clinically. The aims of this study were twofold. Firstly, to design a personalized prosthetic total joint replacement for the treatment of a patient's end-stage temporomandibular joint osteoarthritis, to implant the prosthesis into the patient, and assess clinical outcome 12-months post-operatively; and secondly, to evaluate the influence of changes in prosthetic condyle geometry on implant load response during mastication. A 48-year-old female patient with Grade-5 osteoarthritis to the left temporomandibular joint was recruited, and a prosthesis developed to match the native temporomandibular joint anatomy. The prosthesis was 3D printed, sterilized and implanted into the patient, and pain and function measured 12-months post-operatively. The prosthesis load response during a chewing-bite and maximum-force bite was evaluated using a personalized multi-body musculoskeletal model. Simulations were performed after perturbing condyle thickness, neck length and head sphericity. Increases in prosthetic condyle neck length malaligned the mandible and perturbed temporomandibular joint force. Changes in condylar component thickness greatly influenced fixation screw stress response, while a more eccentric condylar head increased prosthetic joint-contact loading. Post-operatively, the prosthetic temporomandibular joint surgery reduced patient pain from 7/10 to 1/10 on a visual analog scale, and increased intercisal opening distance from 22 mm to 38 mm. This study demonstrates effectiveness of a personalized prosthesis that may ultimately be adapted to treat a wide-range of end-stage temporomandibular joint conditions, and highlights sensitivity of prosthesis load response to changes in condylar geometry. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Effect of changes of femoral offset on abductor and joint reaction forces in total hip arthroplasty.

    PubMed

    Rüdiger, Hannes A; Guillemin, Maïka; Latypova, Adeliya; Terrier, Alexandre

    2017-11-01

    Anatomical reconstruction in total hip arthroplasty (THA) allows for physiological muscle function, good functional outcome and implant longevity. Quantitative data on the effect of a loss or gain of femoral offset (FO) are scarce. The aim of this study was to quantitatively describe the effect of FO changes on abductor moment arms, muscle and joint reactions forces. THA was virtually performed on 3D models built from preoperative CT scans of 15 patients undergoing THA. Virtual THA was performed with a perfectly anatomical reconstruction, a loss of 20% of FO (-FO), and a gain of 20% of FO (+FO). These models were combined with a generic musculoskeletal model (OpenSim) to predict moment arms, muscle and joint reaction forces during normal gait cycles. In average, with -FO reconstructions, muscle moment arms decreased, while muscle and hip forces increased significantly (p < 0.001). We observed the opposite with +FO reconstructions. Gluteus medius was more affected than gluteus minimus. -FO had more effect than +FO. A change of 20% of FO induced an average change 8% of abductor moment arms, 16% of their forces, and 6% of the joint reaction force. To our knowledge, this is the first report providing quantitative data on the effect of FO changes on muscle and joint forces during normal gait. A decrease of FO necessitates an increase of abductor muscle force to maintain normal gait, which in turn increases the joint reaction force. This effect underscores the importance of an accurate reconstruction of the femoral offset.

  3. Joint Laxity in Preschool Children Born Preterm.

    PubMed

    Romeo, Domenico M; Velli, Chiara; Lucibello, Simona; Ferrantini, Gloria; Leo, Giuseppina; Brogna, Claudia; Cota, Francesco; Ricci, Daniela; Gallini, Francesca; Romagnoli, Costantino; Vento, Giovanni; Mercuri, Eugenio

    2018-06-01

    To evaluate the prevalence of joint laxity in children born preterm assessed in the first 2 years, the relationship between joint laxity and motor performance at preschool age, and possible changes over time in a subgroup of children followed longitudinally. The revised scale of Beighton Score was used to evaluate joint laxity in a population of 132 preschool children born preterm between 24 and 32 weeks of gestational age. All were assessed for joint laxity between 12 and 24 months of age. Children also performed the Movement Assessment Battery for Children-Second Edition between the age of 3 years and 6 months and 4 years; the age at onset of independent walking also was recorded. The total Beighton Score ranged between 0 and 8. Twenty percent of the cohort showed joint laxity. No differences related to sex or gestational age were observed. Children born preterm with joint laxity achieved later independent walking and achieved lower scores on Movement Assessment Battery for Children-Second Edition than those without joint laxity. In 76 children born preterm, an assessment for joint laxity was repeated once between 25 and 36 months and again after >36 months. No statistically significant difference was observed between the 3 assessments. The Beighton Score can be used to assess generalized joint laxity in children born preterm. As the presence of joint laxity influenced motor competences, the possibility to early identify these infants in the first 2 years is of interest to benefit from early intervention and potentially improve gross motor skills and coordination. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Joint swelling

    MedlinePlus

    ... of arthritis caused by buildup of uric acid crystals in a joint ( gout ) Arthritis caused by wear ... osteoarthritis ) Arthritis caused by buildup of calcium-type crystals in joints ( pseudogout ) Disorder that involves arthritis and ...

  5. The joint flanker effect and the joint Simon effect: On the comparability of processes underlying joint compatibility effects.

    PubMed

    Dittrich, Kerstin; Bossert, Marie-Luise; Rothe-Wulf, Annelie; Klauer, Karl Christoph

    2017-09-01

    Previous studies observed compatibility effects in different interference paradigms such as the Simon and flanker task even when the task was distributed across two co-actors. In both Simon and flanker tasks, performance is improved in compatible trials relative to incompatible trials if one actor works on the task alone as well as if two co-actors share the task. These findings have been taken to indicate that actors automatically co-represent their co-actor's task. However, recent research on the joint Simon and joint flanker effect suggests alternative non-social interpretations. To which degree both joint effects are driven by the same underlying processes is the question of the present study, and it was scrutinized by manipulating the visibility of the co-actor. While the joint Simon effect was not affected by the visibility of the co-actor, the joint flanker effect was reduced when participants did not see their co-actors but knew where the co-actors were seated. These findings provide further evidence for a spatial interpretation of the joint Simon effect. In contrast to recent claims, however, we propose a new explanation of the joint flanker effect that attributes the effect to an impairment in the focusing of spatial attention contingent on the visibility of the co-actor.

  6. Relationship between leg extensor muscle strength and knee joint loading during gait before and after total knee arthroplasty.

    PubMed

    Vahtrik, Doris; Gapeyeva, Helena; Ereline, Jaan; Pääsuke, Mati

    2014-01-01

    The aim of the present study was to evaluate an isometric maximal voluntary contraction (MVC) force of the leg extensor muscles and its relationship with knee joint loading during gait prior and after total knee arthroplasty (TKA). Custom-made dynamometer was used to assess an isometric MVC force of the leg extensor muscles and 3-D motion analysis system was used to evaluate the knee joint loading during gait in 13 female patients (aged 49-68 years) with knee osteoarthritis. Patients were evaluated one day before, and three and six months following TKA in the operated and non-operated leg. Six months after TKA, MVC force of the leg extensor muscles for the operated leg did not differ significantly as compared to the preoperative level, whereas it remained significantly lower for the non-operated leg and controls. The knee flexion moment and the knee joint power during mid stance of gait was improved six months after TKA, remaining significantly lowered compared with controls. Negative moderate correlation between leg extensor muscles strength and knee joint loading for the operated leg during mid stance was noted three months after TKA. The correlation analysis indicates that due to weak leg extensor muscles, an excessive load is applied to knee joint during mid stance of gait in patients, whereas in healthy subjects stronger knee-surrounding muscles provide stronger knee joint loading during gait. III (correlational study). Copyright © 2013 Elsevier B.V. All rights reserved.

  7. A Modelling Method of Bolt Joints Based on Basic Characteristic Parameters of Joint Surfaces

    NASA Astrophysics Data System (ADS)

    Yuansheng, Li; Guangpeng, Zhang; Zhen, Zhang; Ping, Wang

    2018-02-01

    Bolt joints are common in machine tools and have a direct impact on the overall performance of the tools. Therefore, the understanding of bolt joint characteristics is essential for improving machine design and assembly. Firstly, According to the experimental data obtained from the experiment, the stiffness curve formula was fitted. Secondly, a finite element model of unit bolt joints such as bolt flange joints, bolt head joints, and thread joints was constructed, and lastly the stiffness parameters of joint surfaces were implemented in the model by the secondary development of ABAQUS. The finite element model of the bolt joint established by this method can simulate the contact state very well.

  8. Patterns of Ninety-Day Readmissions Following Total Joint Replacement in a Bundled Payment Initiative.

    PubMed

    Behery, Omar A; Kester, Benjamin S; Williams, Jarrett; Bosco, Joseph A; Slover, James D; Iorio, Richard; Schwarzkopf, Ran

    2017-04-01

    Alternative payment models aim to improve quality and decrease costs associated with total joint replacement. Postoperative readmissions within 90 days are of interest to clinicians and administrators as there is no additional reimbursement beyond the episode bundled payment target price. The aim of this study is to improve the understanding of the patterns of readmission which would better guide perioperative patient management affecting readmissions. We hypothesize that readmissions have different timing, location, and patient health profile patterns based on whether the readmission is related to a medical or surgical diagnosis. A retrospective cohort of 80 readmissions out of 1412 total joint replacement patients reimbursed through a bundled payment plan was analyzed. Patients were grouped by readmission diagnosis (surgical or medical) and the main variables analyzed were time to readmission, location of readmission, and baseline Perioperative Orthopaedic Surgical Home and American Society of Anesthesiologists scores capturing pre-existing state of health. Nonparametric tests and multivariable regressions were used to test associations. Surgical readmissions occurred earlier than medical readmissions (mean 18 vs 33 days, P = .011), and were more likely to occur at the hospital where the surgery was performed (P = .035). Perioperative Orthopaedic Surgical Home and American Society of Anesthesiologists scores did not predict medical vs surgical readmissions (P = .466 and .879) after adjusting for confounding variables. Readmissions appear to follow different patterns depending on whether they are surgical or medical. Surgical readmissions occur earlier than medical readmissions, and more often at the hospital where the surgery was performed. The results of this study suggest that these 2 types of readmissions have different patterns with different implications toward perioperative care and follow-up after total joint replacement. Copyright © 2016 Elsevier Inc

  9. Subtalar joint stress imaging with tomosynthesis.

    PubMed

    Teramoto, Atsushi; Watanabe, Kota; Takashima, Hiroyuki; Yamashita, Toshihiko

    2014-06-01

    The purpose of this study was to perform stress imaging of hindfoot inversion and eversion using tomosynthesis and to assess the subtalar joint range of motion (ROM) of healthy subjects. The subjects were 15 healthy volunteers with a mean age of 29.1 years. Coronal tomosynthesis stress imaging of the subtalar joint was performed in a total of 30 left and right ankles. A Telos stress device was used for the stress load, and the load was 150 N for both inversion and eversion. Tomographic images in which the posterior talocalcaneal joint could be confirmed on the neutral position images were used in measurements. The angle of the intersection formed by a line through the lateral articular facet of the posterior talocalcaneal joint and a line through the surface of the trochlea of the talus was measured. The mean change in the angle of the calcaneus with respect to the talus was 10.3 ± 4.8° with inversion stress and 5.0 ± 3.8° with eversion stress from the neutral position. The result was a clearer depiction of the subtalar joint, and inversion and eversion ROM of the subtalar joint was shown to be about 15° in healthy subjects. Diagnostic, Level IV.

  10. Joint Attention Revisited: Finding Strengths among Children with Autism

    ERIC Educational Resources Information Center

    Hurwitz, Sarah; Watson, Linda R.

    2016-01-01

    Differences in joint attention are prominent for some children with autism and are often used as an indicator of the disorder. This study examined the joint attention competencies of young children with autism who demonstrated joint attention ability and compared them to children with developmental delays. A total of 40 children with autism and…

  11. Mutual coordination strengthens the sense of joint agency in cooperative joint action.

    PubMed

    Bolt, Nicole K; Poncelet, Evan M; Schultz, Benjamin G; Loehr, Janeen D

    2016-11-01

    Philosophers have proposed that when people coordinate their actions with others they may experience a sense of joint agency, or shared control over actions and their effects. However, little empirical work has investigated the sense of joint agency. In the current study, pairs coordinated their actions to produce tone sequences and then rated their sense of joint agency on a scale ranging from shared to independent control. People felt more shared than independent control overall, confirming that people experience joint agency during joint action. Furthermore, people felt stronger joint agency when they (a) produced sequences that required mutual coordination compared to sequences in which only one partner had to coordinate with the other, (b) held the role of follower compared to leader, and (c) were better coordinated with their partner. Thus, the strength of joint agency is influenced by the degree to which people mutually coordinate with each other's actions. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Joint Chiefs of Staff > Leadership

    Science.gov Websites

    Senior Enlisted Advisor Joint Staff History Joint Staff Inspector General Joint Staff Structure Origin of J8 | Force Structure, Resources & Assessment Contact Joint Staff Structure Joint Staff Organizational Chart Joint Chiefs of Staff Links Home Today in DOD About DOD Top Issues News Photos/Videos

  13. The effect of mindfulness training prior to total joint arthroplasty on post-operative pain and physical function: study protocol for a randomised controlled trial.

    PubMed

    Dowsey, Michelle M; Castle, David J; Knowles, Simon R; Monshat, Kaveh; Salzberg, Michael R; Choong, Peter F M

    2014-06-05

    Osteoarthritis is a leading cause of disability in developed nations. In Australia it afflicts 16.5% of the adult population. Total joint arthroplasty is considered the treatment of choice for end stage osteoarthritis. The number of total joint arthroplasties undertaken in Australia has doubled over the last decade (more than 80,000 procedures in 2011). The incidence of pre-operative psychological distress in this group of patients is reported between 30% and 60% and pre-operative psychological distress is associated with poorer pain and functional outcomes after surgery. This study will use a mindfulness-based psychological intervention to enhance outcomes in people undergoing total joint arthroplasty and, in addition, will test hypotheses about coping with chronic illness in an aged population. This study is the first of its kind and will provide a greater understanding of the role of a mental health enhancement program on the physical recovery of total joint arthroplasty patients. One hundred and fifty people with end-stage arthritis on the waiting list for total hip or knee arthroplasty will be recruited and randomly allocated to one of two groups using computer-generated block randomisation. A randomised controlled trial adhering to CONSORT guidelines will evaluate the efficacy of a mindfulness training program (weekly group-based classes in mindfulness practice, 2 ½ hours, for 8 weeks plus a 7-hour Saturday session in Week 6) prior to total joint arthroplasty, compared to a "standard care" group who will undergo routine total joint arthroplasty. Primary outcomes will be evaluated by a blinded examiner at baseline, 3 and 12 months post-surgery, using a validated self-reported pain and physical function scale. Secondary outcomes will include i) a range of validated measures of psychological wellbeing and ii) health economic analysis. All analyses will be conducted on an intention to treat basis using linear regression models. Health economic modelling will

  14. Signaling networks in joint development

    PubMed Central

    Salva, Joanna E.; Merrill, Amy E.

    2016-01-01

    Here we review studies identifying regulatory networks responsible for synovial, cartilaginous, and fibrous joint development. Synovial joints, characterized by the fluid-filled synovial space between the bones, are found in high-mobility regions and are the most common type of joint. Cartilaginous joints unite adjacent bones through either a hyaline cartilage or fibrocartilage intermediate. Fibrous joints, which include the cranial sutures, form a direct union between bones through fibrous connective tissue. We describe how the distinct morphologic and histogenic characteristics of these joint classes are established during embryonic development. Collectively, these studies reveal that despite the heterogeneity of joint strength and mobility, joint development throughout the skeleton utilizes common signaling networks via long-range morphogen gradients and direct cell-cell contact. This suggests that different joint types represent specialized variants of homologous developmental modules. Identifying the unifying aspects of the signaling networks between joint classes allows a more complete understanding of the signaling code for joint formation, which is critical to improving strategies for joint regeneration and repair. PMID:27859991

  15. Joint awareness in osteoarthritis of the hip and knee evaluated with the 'Forgotten Joint' Score before and after joint replacement.

    PubMed

    Thienpont, E; Vanden Berghe, A; Schwab, P E; Forthomme, J P; Cornu, O

    2016-10-01

    To utilize the 'Forgotten Joint' Score (FJS), a 12-item questionnaire analysing the ability to forget the joint, for comparing preoperative status in osteoarthritic patients scheduled for total hip arthroplasty (THA) or total knee arthroplasty (TKA). Higher scores represent a better result with a maximum of 100. The hypothesis of this study was that a preoperative difference in favour of hip arthritis could eventually explain why THA is cited more often as a forgotten joint than TKA. A prospective cohort study was conducted in 150 patients with either tricompartmental knee (n = 75) or hip osteoarthritis (n = 75). Patients completed FJS-12 scores preoperatively and 1 year postoperatively. A similar preoperative FJS-12 was observed for hip (22 (15)) and knee osteoarthritis (24 (17)) (n.s.). The postoperative FJS-12 score was significantly higher for THA (80 (24)) than for TKA (70 (27)) (p < 0.05). High reliability after 6 weeks was observed for the preoperative FJS-12 test-retest reliability (ICC = 0.87) in TKA. A preoperative floor effect of 15 % in THA and 0 % in TKA was found as well as a postoperative ceiling effect of 33 % in THA and 9 % in TKA. The clinical relevance of utilizing the FJS-12 as an instrument to evaluate outcome is strongly proposed for knee arthroplasty. In general, one is not aware of a healthy joint during the ADL, and it can therefore be regarded as 'forgotten'. The preoperative FJS-12 Score is a powerful tool to provide patients with clearer insights into their positive evolution after surgery. The use of the FJS-12 in THA is a topic for further research, as this study found that floor and ceiling effects limit its usefulness in studies evaluating clinical outcome in this area. II.

  16. Length of Stay in Skilled Nursing Facilities Following Total Joint Arthroplasty.

    PubMed

    Haghverdian, Brandon A; Wright, David J; Schwarzkopf, Ran

    2017-02-01

    The most commonly used postacute care facility after total joint arthroplasty is a skilled nursing facility (SNF). However, little is known regarding the role of physical therapy achievements and insurance status on the decision to discharge from an SNF. In this study, we aim to compare functional outcomes and length of stay (LOS) at an SNF among patients with Medicare vs private health coverage. We retrospectively collected physical therapy data for 114 patients who attended an SNF following acute hospitalization for total joint arthroplasty. Medicare beneficiaries were compared with patients covered by Managed Care (MC) policies (health maintenance organization [HMO] and preferred provider organization [PPO]) using several SNF discharge outcomes, including LOS, distance ambulated, and functional independence in gait, transfers, and bed mobility. LOS at the SNF was significantly longer for Medicare patients (Medicare: 24 ± 22 days, MC: 12 ± 7 days, P = .007). After adjusting for LOS and covariates, MC patients had significantly greater achievements in all functional outcomes measured. In a study subanalysis, Medicare patients were found to achieve similar functional outcomes by SNF day 14 as MC patients achieved by their day of discharge on approximately day 12. Yet, the Medicare group was not discharged until several days later. Medicare status is associated with poor functional outcomes, long LOS, and slow progress in the SNF. Our results suggest that insurance reimbursement may be a primary factor in the decision to discharge, rather than the achievement of functional milestones. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Patients' journeys through total joint replacement: patterns of medication use.

    PubMed

    Johnson, Emma C; Horwood, Jeremy; Gooberman-Hill, Rachael

    2014-06-01

    Medication is used to manage pain that results from both osteoarthritis and total joint replacement (TJR). Research has provided insight into how people living with osteoarthritis use pain relief medication. However, it is not known whether elective TJR affects existing attitudes and behaviours with regard to pain medications. Using qualitative methods, the present study explored patterns of pain relief use around the time of TJR. In-depth face-to-face qualitative interviews were carried out with 24 patients two to four weeks after they had undergone TJR for hip or knee osteoarthritis. Participants were asked to reflect on their use of pain medication pre-surgery, while in hospital and while recovering from their operation at home. Transcripts of the audio-recorded interviews were imported into Atlas.ti® and thematic analysis was used. Attitudes to pain relief medication and their use are not static. Many participants change their use of pain medication around the time of surgery. This shift was influenced by interactions with health professionals and changing views on the acceptability, necessity and value of pain relief in helping to manage an altered pain experience. Understanding reasons for medication-taking behaviour during the journey through joint replacement may be helpful to health professionals. Health professionals have a fundamental role to play in challenging or reinforcing different treatment beliefs, which is the basis for effective use of pain relief over the pre- to postoperative period. © 2013 John Wiley & Sons, Ltd.

  18. Increased Complications for Schizophrenia and Bipolar Disorder Patients Undergoing Total Joint Arthroplasty.

    PubMed

    Kheir, Michael M; Kheir, You Na P; Tan, Timothy L; Ackerman, Colin T; Rondon, Alexander J; Chen, Antonia F

    2018-05-01

    Although it has been shown that anxiety and depression are associated with increased complications after total joint arthroplasty (TJA), the outcomes of TJA in patients with a history of psychosis are unknown. This study evaluated the influence of bipolar and schizophrenic disorders on complications after TJA, particularly aseptic and septic revisions. A retrospective review of 156 TJAs (125 primaries and 31 revisions) was performed at a single institution from 2000 to 2015. Bipolar and schizophrenic patients were identified based on International Classification of Diseases, Ninth Revision codes or by those actively taking anti-psychotic medications, followed by manual chart review to confirm diagnoses. The psychosis patient cohort was matched 3:1 for a variety of factors. Revisions and readmissions were evaluated. Survivorship curves were generated. Patients with schizophrenia or bipolar disorder had an increased odds of developing peri-prosthetic joint infection at 90 days (odds ratio [OR] 3.34, P = .049), 2 years (OR 3.94, P = .004), and at any time point (OR 4.32, P = .002). Psychosis patients had increased odds of aseptic and mechanical revisions at all endpoints, particularly from dislocation. Psychosis patients had a higher number of post-operative emergency department visits (P < .001), and were more likely to be discharged to a rehabilitation facility (P < .001). Patients with bipolar affective disorder or schizophrenia may have multiple barriers to self-care after TJA, and are at an increased risk for undergoing revision TJA for prosthetic joint infection and mechanical causes. Increased pre-operative education and screening of this patient population may be necessary prior to performing TJA. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Temporal gene expression profiling of the rat knee joint capsule during immobilization-induced joint contractures.

    PubMed

    Wong, Kayleigh; Sun, Fangui; Trudel, Guy; Sebastiani, Paola; Laneuville, Odette

    2015-05-26

    Contractures of the knee joint cause disability and handicap. Recovering range of motion is recognized by arthritic patients as their preference for improved health outcome secondary only to pain management. Clinical and experimental studies provide evidence that the posterior knee capsule prevents the knee from achieving full extension. This study was undertaken to investigate the dynamic changes of the joint capsule transcriptome during the progression of knee joint contractures induced by immobilization. We performed a microarray analysis of genes expressed in the posterior knee joint capsule following induction of a flexion contracture by rigidly immobilizing the rat knee joint over a time-course of 16 weeks. Fold changes of expression values were measured and co-expressed genes were identified by clustering based on time-series analysis. Genes associated with immobilization were further analyzed to reveal pathways and biological significance and validated by immunohistochemistry on sagittal sections of knee joints. Changes in expression with a minimum of 1.5 fold changes were dominated by a decrease in expression for 7732 probe sets occurring at week 8 while the expression of 2251 probe sets increased. Clusters of genes with similar profiles of expression included a total of 162 genes displaying at least a 2 fold change compared to week 1. Functional analysis revealed ontology categories corresponding to triglyceride metabolism, extracellular matrix and muscle contraction. The altered expression of selected genes involved in the triglyceride biosynthesis pathway; AGPAT-9, and of the genes P4HB and HSP47, both involved in collagen synthesis, was confirmed by immunohistochemistry. Gene expression in the knee joint capsule was sensitive to joint immobility and provided insights into molecular mechanisms relevant to the pathophysiology of knee flexion contractures. Capsule responses to immobilization was dynamic and characterized by modulation of at least three

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

    PubMed Central

    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 (p<0.05). No differences were observed for peak joint compressive forces between groups. Some muscle force compensatory strategies appear to be present in both the loading and push-off phases. Evidence from knee 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

  1. Novel joint cupping clinical maneuver for ultrasonographic detection of knee joint effusions.

    PubMed

    Uryasev, Oleg; Joseph, Oliver C; McNamara, John P; Dallas, Apostolos P

    2013-11-01

    Knee effusions occur due to traumatic and atraumatic causes. Clinical diagnosis currently relies on several provocative techniques to demonstrate knee joint effusions. Portable bedside ultrasonography (US) is becoming an adjunct to diagnosis of effusions. We hypothesized that a US approach with a clinical joint cupping maneuver increases sensitivity in identifying effusions as compared to US alone. Using unembalmed cadaver knees, we injected fluid to create effusions up to 10 mL. Each effusion volume was measured in a lateral transverse location with respect to the patella. For each effusion we applied a joint cupping maneuver from an inferior approach, and re-measured the effusion. With increased volume of saline infusion, the mean depth of effusion on ultrasound imaging increased as well. Using a 2-mm cutoff, we visualized an effusion without the joint cupping maneuver at 2.5 mL and with the joint cupping technique at 1 mL. Mean effusion diameter increased on average 0.26 cm for the joint cupping maneuver as compared to without the maneuver. The effusion depth was statistically different at 2.5 and 7.5 mL (P < .05). Utilizing a joint cupping technique in combination with US is a valuable tool in assessing knee effusions, especially those of subclinical levels. Effusion measurements are complicated by uneven distribution of effusion fluid. A clinical joint cupping maneuver concentrates the fluid in one recess of the joint, increasing the likelihood of fluid detection using US. © 2013 Elsevier Inc. All rights reserved.

  2. Effect of joint spacing and joint dip on the stress distribution around tunnels using different numerical methods

    NASA Astrophysics Data System (ADS)

    Nikadat, Nooraddin; Fatehi Marji, Mohammad; Rahmannejad, Reza; Yarahmadi Bafghi, Alireza

    2016-11-01

    Different conditions may affect the stability of tunnels by the geometry (spacing and orientation) of joints in the surrounded rock mass. In this study, by comparing the results obtained by the three novel numerical methods i.e. finite element method (Phase2), discrete element method (UDEC) and indirect boundary element method (TFSDDM), the effects of joint spacing and joint dips on the stress distribution around rock tunnels are numerically studied. These comparisons indicate the validity of the stress analyses around circular rock tunnels. These analyses also reveal that for a semi-continuous environment, boundary element method gives more accurate results compared to the results of finite element and distinct element methods. In the indirect boundary element method, the displacements due to joints of different spacing and dips are estimated by using displacement discontinuity (DD) formulations and the total stress distribution around the tunnel are obtained by using fictitious stress (FS) formulations.

  3. Shear fracture of jointed steel plates of bolted joints under impact load

    NASA Astrophysics Data System (ADS)

    Daimaruya, M.; Fujiki, H.; Ambarita, H.; Kobayashi, H.; Shin, H.-S.

    2013-07-01

    The present study is concerned with the development of a fracture criterion for the impact fracture of jointed steel plates of bolted joints used in a car body, which contributes to crash simulations by CAE. We focus our attention on the shear fracture of the jointed steel plates of lap-bolted joints in the suspension of a car under impact load. Members of lap-bolted joints are modelled as a pair of steel plates connected by a bolt. One of the plates is a specimen subjected to plastic deformation and fracture and the other is a jig subjected to elastic deformation only. Three kinds of steel plate specimens are examined, i.e., a common steel plate with a tensile strength of 270 MPa and high tensile strength steel plates of 440 and 590 MPa used for cars. The impact shear test was performed using the split Hopkinson bar technique for tension impact, together with the static test using a universal testing machine INSTRON 5586. The behaviour of the shear stress and deformation up to rupture taking place in the joint was discussed. The obtained results suggest that a stress-based fracture criterion may be developed for the impact fracture of jointed steel plates of a lap-bolted joint.

  4. Randomized Prospective Trial Comparing the Use of Intravenous versus Oral Acetaminophen in Total Joint Arthroplasty.

    PubMed

    Politi, Joel R; Davis, Richard L; Matrka, Alexis K

    2017-04-01

    Multimodal pain management has had a significant effect on improving total joint arthroplasty recovery and patient satisfaction. There is literature supporting that intravenous (IV) acetaminophen reduces postoperative pain and narcotic use in the total joint population. However, there are no studies comparing the effectiveness of IV vs oral (PO) acetaminophen as part of a standard multimodal perioperative pain regimen. One hundred twenty patients undergoing hip and knee arthroplasty surgeries performed by one joint arthroplasty surgeon were prospectively randomized into 2 groups. Group 1 (63 patients) received IV and group 2 (57 patients) received PO acetaminophen in addition to a standard multimodal perioperative pain regimen. Each group received 1 gram of acetaminophen preoperatively and then every 6 hours for 24 hours. Total narcotic use and visual analog scale (VAS) scores were collected every 4 hours postoperatively. The 24-hour average hydromorphone equivalents given were not different between groups (3.71 vs 3.48) at 24 hours (P = .76), or at any of the individual 4-hour intervals. The 24-hour average visual analog scale scores in group 1 (IV) was 3.00 and in group 2 (PO) was 3.40 (P = .06). None of the 4-hour intervals were significantly different except the first interval (0-4 hour postoperatively), which favored the IV group (P = .03). The use of IV acetaminophen may have a role when given intraoperatively to reduce the immediate pain after surgery. Following that, it does not provide a significant benefit in reducing pain or narcotic use when compared with the much less expensive PO form. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Results of arthroscopic joint debridement in different stages of chondromalacia of the knee joint.

    PubMed

    Krüger, T; Wohlrab, D; Birke, A; Hein, W

    2000-01-01

    A retrospective study was performed of 161 patients who had undergone arthroscopic operation for chondromalacia of the knee joint. After an average follow-up period of 40 (range 10-72) months, patients with severe articular cartilage lesions who had undergone articular lavage alone showed significantly poorer results (P < 0.001). With the same stage of chondromalacia and having undergone the same surgical procedure, younger patients showed better results than older patients. The more effective interruption of the circulus vitiosus during the development of degenerative joint diseases is the primary cause for better results achieved by mechanical debridement of the joint for patients suffering from grade 2 or higher. According to the literature, aggressive subchondral abrasion in severely degenerated knees does not show any benefits. Apparently, the success of the therapy depends to a great extent on the inferiority of the potential degenerative regenerate (lack of capacity of intrinsic regeneration of the hyaline cartilage) as well as on the grade and the progression of chondromalacia. Almost every second patient suffering from grade 4 chondromalacia complained of recurrent pain 1 year postoperatively. One of every 6 patients received a knee joint prosthesis within the 1st year. Therefore, the patients' preoperative expectations have to be clearly objectified. The surgical procedure as an operation with a low complication risk can also be justified as a temporary alternative to total knee arthroplasty in patients suffering from a high-grade degeneration of the joint.

  6. Joint Improvised Explosive Device Defeat Organization Annual Report 2010

    DTIC Science & Technology

    2010-01-01

    Fox is an effort to characterize a COTS, man-portable, radiography system exceeding current EOD radiography penetration capabilities. Gray Fox... rocket propelled grenades at a reduced weight compared to currently available armor solutions. Sentinel Scout. This developmental appliqué kit is...Dismounted System Joint Electronic warfare Cour&e Joint Total Entity Tracking for the Instrumented Battlefield Joint Readinoss Training Contor

  7. Lower limb joint moment during walking in water.

    PubMed

    Miyoshi, Tasuku; Shirota, Takashi; Yamamoto, Shin-Ichiro; Nakazawa, Kimitaka; Akai, Masami

    2003-11-04

    Walking in water is a widely used rehabilitation method for patients with orthopedic disorders or arthritis, based on the belief that the reduction of weight in water makes it a safer medium and prevents secondary injuries of the lower-limb joints. To our knowledge, however, no experimental data on lower-limb joint moment during walking in water is available. The aim of this study was to quantify the joint moments of the ankle, knee, and hip during walking in water in comparison with those on land. Eight healthy volunteers walked on land and in water at a speed comfortable for them. A video-motion analysis system and waterproof force platform were used to obtain kinematic data and to calculate the joint moments. The hip joint moment was shown to be an extension moment almost throughout the stance phase during walking in water, while it changed from an extension- to flexion-direction during walking on land. The knee joint moment had two extension peaks during walking on land, whereas it had only one extension peak, a late one, during walking in water. The ankle joint moment during walking in water was considerably reduced but in the same direction, plantarflexion, as that during walking on land. The joint moments of the hip, knee, and ankle were not merely reduced during walking in water; rather, inter-joint coordination was totally changed.

  8. Early, asymptomatic stage of degenerative joint disease in canine hip joints.

    PubMed

    Lust, G; Summers, B A

    1981-11-01

    The early stages of degenerative joint disease were investigated in coxofemoral joints from dogs with a hereditary predisposition to hip dysplasia. Alterations observed included mild nonsuppurative synovitis, increased volume of both synovial fluid and the ligamentum teres, and focal degenerative articular cartilage lesions. On radiologic examination, subluxation of the femoral head was seen, but only in the most severely affected joints. Synovial inflammation with increased synovial fluid and ligament volumes were indicators of early degenerative joint disease in dogs. These changes seemed to coincide with, or perhaps to precede, microscopic evidence for articular cartilage degeneration and occurred before radiologic abnormalities were detected.

  9. Joint Contact Stress

    PubMed Central

    Brand, Richard A

    2005-01-01

    A joint's normal mechanical history contributes to the maintenance of articular cartilage and underlying bone. Loading facilitates the flow of nutrients into cartilage and waste products away, and additionally provides the mechanical signals essential for normal cell and tissue maintenance. Deleteriously low or high contact stresses have been presumed to result in joint deterioration, and particular aspects of the mechanical environment may facilitate repair of damaged cartilage. For decades, investigators have explored static joint contact stresses (under some more or less arbitrary condition) as a surrogate of the relevant mechanical history. Contact stresses have been estimated in vitro in many joints and in a number of species, although only rarely in vivo. Despite a number of widely varying techniques (and spatial resolutions) to measure these contact stresses, reported ranges of static peak normal stresses are relatively similar from joint to joint across species, and in the range of 0.5 to 5.0 MPa. This suggests vertebrate diarthrodial joints have evolved to achieve similar mechanical design criteria. Available evidence also suggests some disorders of cartilage deterioration are associated with somewhat higher peak pressures ranging from 1-20 MPa, but overlapping the range of normal pressures. Some evidence and considerable logic suggests static contact stresses per se do not predict cartilage responses, but rather temporal aspects of the contact stress history. Static contact stresses may therefore not be a reasonable surrogate for biomechanical studies. Rather, temporal and spatial aspects of the loading history undoubtedly induce beneficial and deleterious biological responses. Finally, since all articular cartilage experiences similar stresses, the concept of a "weight-bearing" versus a "non-weight-bearing" joint seems flawed, and should be abandoned. PMID:16089079

  10. Bundled Payments in Total Joint Replacement: Keeping Our Care Affordable and High in Quality.

    PubMed

    McLawhorn, Alexander S; Buller, Leonard T

    2017-09-01

    The purpose of this review was to evaluate the literature regarding bundle payment reimbursement models for total joint arthroplasty (TJA). From an economic standpoint, TJA are cost-effective, but they represent a substantial expense to the Centers for Medicare & Medicaid Services (CMS). Historically, fee-for-service payment models resulted in highly variable cost and quality. CMS introduced Bundled Payments for Care Improvement (BPCI) in 2012 and subsequently the Comprehensive Care for Joint Replacement (CJR) reimbursement model in 2016 to improve the value of TJA from the perspectives of both CMS and patients, by improving quality via cost control. Early results of bundled payments are promising, but preserving access to care for patients with high comorbidity burdens and those requiring more complex care is a lingering concern. Hospitals, regardless of current participation in bundled payments, should develop care pathways for TJA to maximize efficiency and patient safety.

  11. [Total Joint Replacement and Return to Sports].

    PubMed

    Oehler, N; Schmidt, T; Niemeier, A

    2016-12-01

    Background: An increasing number of physically active patients not only need to know if they will basically be able to engage in sports after undergoing arthroplasty. They also would like to know whether or not they will be able to resume their preoperative activity levels. This article aims to provide an overview of recent data regarding the following questions on hip, knee and shoulder arthroplasty: (1) What is the impact of physical activity on an endoprosthesis? (2) What level of sports can be achieved after an arthroplasty procedure? (3) What types of sport are recommended for patients with an endoprosthesis? Methods: PubMed-based review of the literature. Narrative review focusing on current data from the years 2010 to 2016. Results: The commonly known recommendation to exercise low-impact sports such as hiking, swimming, cycling or golf at a moderate intensity remains valid for all types of prostheses in all joints. There is broad consensus that the benefits of these sports outweigh the negative effects. Having undergone total hip or knee arthroplasty, most patients with a high preoperative activity level return to sports after 3-6 months, albeit with a clear tendency to lower intensity and a shift from high-impact to low-impact sports. Some key questions have to be answered regarding the effects of low-impact sports that are exercised with high intensity, the effects resulting from high-impact sports, effects specific to different types of sport, and possibilities provided by different prosthesis types. In this context, a lot remains to be done to investigate the limits between positive and negative effects resulting from physical activity of varying intensity. New data suggests that generally a higher physical performance level may be achieved than has been traditionally recommended. Early results of unicondylar knee prostheses are far better than those achieved with bicondylar prostheses. In contrast to expert recommendations, shoulder endoprostheses show

  12. Modeling Progressive Failure of Bonded Joints Using a Single Joint Finite Element

    NASA Technical Reports Server (NTRS)

    Stapleton, Scott E.; Waas, Anthony M.; Bednarcyk, Brett A.

    2010-01-01

    Enhanced finite elements are elements with an embedded analytical solution which can capture detailed local fields, enabling more efficient, mesh-independent finite element analysis. In the present study, an enhanced finite element is applied to generate a general framework capable of modeling an array of joint types. The joint field equations are derived using the principle of minimum potential energy, and the resulting solutions for the displacement fields are used to generate shape functions and a stiffness matrix for a single joint finite element. This single finite element thus captures the detailed stress and strain fields within the bonded joint, but it can function within a broader structural finite element model. The costs associated with a fine mesh of the joint can thus be avoided while still obtaining a detailed solution for the joint. Additionally, the capability to model non-linear adhesive constitutive behavior has been included within the method, and progressive failure of the adhesive can be modeled by using a strain-based failure criteria and re-sizing the joint as the adhesive fails. Results of the model compare favorably with experimental and finite element results.

  13. Knee joint effusion following ipsilateral hip surgery.

    PubMed

    Christodoulou, A G; Givissis, P; Antonarakos, P D; Petsatodis, G E; Hatzokos, I; Pournaras, J D

    2010-12-01

    To correlate patellar reflex inhibition with sympathetic knee joint effusion. 65 women and 40 men aged 45 to 75 (mean, 65) years underwent hip surgery. The surgery entailed dynamic hip screw fixation using the lateral approach with reflection of the vastus lateralis for pertrochantric fractures (n = 49), and hip hemiarthroplasty or total hip replacement using the Watson-Jones approach (n = 38) or hip hemiarthroplasty using the posterior approach (n = 18) for subcapital femoral fractures (n = 28) or osteoarthritis (n = 28). Knee joint effusion, patellar reflex, and thigh circumference were assessed in both legs before and after surgery (at day 0.5, 2, 7, 14, 30, and 45). Time-sequence plots were used for chronological analysis, and correlation between patellar reflex inhibition and knee joint effusion was tested. In the time-sequence plot, the peak frequency of patellar reflex inhibition (on day 0.5) preceded that of the knee joint effusion and the thigh circumference increase (on day 2). Patellar reflex inhibition correlated positively with the knee joint effusion (r = 0.843, p = 0.035). These 2 factors correlated significantly for all 3 surgical approaches (p < 0.0005). All 3 approaches were associated with patellar reflex inhibition on day 0.5 (p = 0.033) and knee joint effusion on day 2 (p = 0.051). Surgical trauma of the thigh may cause patellar reflex inhibition and subsequently knee joint effusion.

  14. Modeling of Human Joint Structures.

    DTIC Science & Technology

    1982-09-01

    Acromioclavicular Joint .... ............. ... 20 Glenohumeral Joint .... ................ . 20 HIP JOINT .................. ...... 21 Iliofemoral Ligament...clavicle articulates with the manubrium of the sternum, and the acromioclavicular joint, where the clavicle articulates with the acromion process of the...the interclavicular ligament. Acromioclavicular Joint This articulation between the distal end of the clavicle and the acromion of the scapula is

  15. Intraoperative Considerations for Treatment/Prevention of Prosthetic Joint Infection.

    PubMed

    Suleiman, Linda I; Mesko, Daniel R; Nam, Denis

    2018-06-23

    Innovative measures have recently been proposed to prevent periprosthetic joint infection following total hip and knee arthroplasty. We sought to review these recent innovations to determine the reported reduction in periprosthetic joint infection. The most recent literature demonstrates promising results in regard to hydrofiber dressings as an independent risk factor for primary prosthetic joint infection reduction, which in turn is also linked with cost savings. As our understanding of safe yet effective concentrations of antiseptic solutions develops, dilute betadine in particular has demonstrated encouraging efficacy which warrants continued investigation through controlled trials. In summary, we found that the application of a hydrofiber dressing may prove beneficial in decreasing the risk of prosthetic joint infection following primary total hip and knee arthroplasty. The gold standard for an infection prevention protocol continues to be explored and optimized.

  16. Joint Chiefs of Staff > Media

    Science.gov Websites

    Senior Enlisted Advisor Joint Staff History Joint Staff Inspector General Joint Staff Structure Origin of J8 | Force Structure, Resources & Assessment Contact Joint Staff Media News Videos Chairman's

  17. Experimental joint immobilization in guinea pigs. Effects on the knee joint

    NASA Technical Reports Server (NTRS)

    Marcondesdesouza, J. P.; Machado, F. F.; Sesso, A.; Valeri, V.

    1980-01-01

    In young and adult guinea pigs, the aftermath experimentally induced by the immobilization of the knee joint in hyperextended forced position was studied. Joint immobilization which varied from one to nine weeks was attained by plaster. Eighty knee joints were examined macro and microscopically. Findings included: (1) muscular hypotrophy and joint stiffness in all animals, directly proportional to the length of immobilization; (2) haemoarthrosis in the first week; (3) intra-articular fibrous tissue proliferation ending up with fibrous ankylosis; (4) hyaline articular cartilage erosions; (5) various degrees of destructive menisci changes. A tentative explanation of the fibrous tissue proliferation and of the cartilage changes is offered.

  18. A Review of Natural Joint Systems and Numerical Investigation of Bio-Inspired GFRP-to-Steel Joints

    PubMed Central

    Avgoulas, Evangelos I.; Sutcliffe, Michael P. F.

    2016-01-01

    There are a great variety of joint types used in nature which can inspire engineering joints. In order to design such biomimetic joints, it is at first important to understand how biological joints work. A comprehensive literature review, considering natural joints from a mechanical point of view, was undertaken. This was used to develop a taxonomy based on the different methods/functions that nature successfully uses to attach dissimilar tissues. One of the key methods that nature uses to join dissimilar materials is a transitional zone of stiffness at the insertion site. This method was used to propose bio-inspired solutions with a transitional zone of stiffness at the joint site for several glass fibre reinforced plastic (GFRP) to steel adhesively bonded joint configurations. The transition zone was used to reduce the material stiffness mismatch of the joint parts. A numerical finite element model was used to identify the optimum variation in material stiffness that minimises potential failure of the joint. The best bio-inspired joints showed a 118% increase of joint strength compared to the standard joints. PMID:28773688

  19. A Review of Natural Joint Systems and Numerical Investigation of Bio-Inspired GFRP-to-Steel Joints.

    PubMed

    Avgoulas, Evangelos I; Sutcliffe, Michael P F

    2016-07-12

    There are a great variety of joint types used in nature which can inspire engineering joints. In order to design such biomimetic joints, it is at first important to understand how biological joints work. A comprehensive literature review, considering natural joints from a mechanical point of view, was undertaken. This was used to develop a taxonomy based on the different methods/functions that nature successfully uses to attach dissimilar tissues. One of the key methods that nature uses to join dissimilar materials is a transitional zone of stiffness at the insertion site. This method was used to propose bio-inspired solutions with a transitional zone of stiffness at the joint site for several glass fibre reinforced plastic (GFRP) to steel adhesively bonded joint configurations. The transition zone was used to reduce the material stiffness mismatch of the joint parts. A numerical finite element model was used to identify the optimum variation in material stiffness that minimises potential failure of the joint. The best bio-inspired joints showed a 118% increase of joint strength compared to the standard joints.

  20. Effect of joint mobilization techniques for primary total knee arthroplasty: Study protocol for a randomized controlled trial.

    PubMed

    Xu, Jiao; Zhang, Juan; Wang, Xue-Qiang; Wang, Xuan-Lin; Wu, Ya; Chen, Chan-Cheng; Zhang, Han-Yu; Zhang, Zhi-Wan; Fan, Kai-Yi; Zhu, Qiang; Deng, Zhi-Wei

    2017-12-01

    Total knee arthroplasty (TKA) has become the most preferred procedure by patients for the relief of pain caused by knee osteoarthritis. TKA patients aim a speedy recovery after the surgery. Joint mobilization techniques for rehabilitation have been widely used to relieve pain and improve joint mobility. However, relevant randomized controlled trials showing the curative effect of these techniques remain lacking to date. Accordingly, this study aims to investigate whether joint mobilization techniques are valid for primary TKA. We will manage a single-blind, prospective, randomized, controlled trial of 120 patients with unilateral TKA. Patients will be randomized into an intervention group, a physical modality therapy group, and a usual care group. The intervention group will undergo joint mobilization manipulation treatment once a day and regular training twice a day for a month. The physical modality therapy group will undergo physical therapy once a day and regular training twice a day for a month. The usual care group will perform regular training twice a day for a month. Primary outcome measures will be based on the visual analog scale, the knee joint Hospital for Special Surgery score, range of motion, surrounded degree, and adverse effect. Secondary indicators will include manual muscle testing, 36-Item Short Form Health Survey, Berg Balance Scale function evaluation, Pittsburgh Sleep Quality Index, proprioception, and muscle morphology. We will direct intention-to-treat analysis if a subject withdraws from the trial. The important features of this trial for joint mobilization techniques in primary TKA are randomization procedures, single-blind, large sample size, and standardized protocol. This study aims to investigate whether joint mobilization techniques are effective for early TKA patients. The result of this study may serve as a guide for TKA patients, medical personnel, and healthcare decision makers. It has been registered at http

  1. Laundry joint venture.

    PubMed

    Giancola, D; Voyvodich, M

    1984-12-01

    Many hospitals are concerned about the loss of control which is associated with contracting for linen service. On the the hand, many laundries do not have the resources or experience to serve hospitals in a comprehensive and trouble-free manner. In many communities a joint venture, such as the one described here, can successfully combine the interests of the hospital and laundry communities without causing the hospitals to lose control of the service and without requiring the laundry operator to have detailed knowledge of hospital operations. As more hospitals opt for contract service, and if this service is to be provided at the lowest total cost, the hospitals and the laundries must come to grips with the problems surrounding the laundry-hospital interface. A joint venture, such as that described here, is one way to accomplish this.

  2. Biochemical and biomechanical characterisation of equine cervical facet joint cartilage.

    PubMed

    O'Leary, S A; White, J L; Hu, J C; Athanasiou, K A

    2018-04-15

    The equine cervical facet joint is a site of significant pathology. Located bilaterally on the dorsal spine, these diarthrodial joints work in conjunction with the intervertebral disc to facilitate appropriate spinal motion. Despite the high prevalence of pathology in this joint, the facet joint is understudied and thus lacking in viable treatment options. The goal of this study was to characterise equine facet joint cartilage and provide a comprehensive database describing the morphological, histological, biochemical and biomechanical properties of this tissue. Descriptive cadaver studies. A total of 132 facet joint surfaces were harvested from the cervical spines of six skeletally mature horses (11 surfaces per animal) for compiling biomechanical and biochemical properties of hyaline cartilage of the equine cervical facet joints. Gross morphometric measurements and histological staining were performed on facet joint cartilage. Creep indentation and uniaxial strain-to-failure testing were used to determine the biomechanical compressive and tensile properties. Biochemical assays included quantification of total collagen, sulfated glycosaminoglycan and DNA content. The facet joint surfaces were ovoid in shape with a flat articular surface. Histological analyses highlighted structures akin to articular cartilage of other synovial joints. In general, biomechanical and biochemical properties did not differ significantly between the inferior and superior joint surfaces as well as among spinal levels. Interestingly, compressive and tensile properties of cervical facet articular cartilage were lower than those of articular cartilage from other previously characterised equine joints. Removal of the superficial zone reduced the tissue's tensile strength, suggesting that this zone is important for the tensile integrity of the tissue. Facet surfaces were sampled at a single, central location and do not capture the potential topographic variation in cartilage properties. This

  3. Effect of Strain Rate on Joint Strength and Failure Mode of Lead-Free Solder Joints

    NASA Astrophysics Data System (ADS)

    Lin, Jian; Lei, Yongping; Fu, Hanguang; Guo, Fu

    2018-03-01

    In surface mount technology, the Sn-3.0Ag-0.5Cu solder joint has a shorter impact lifetime than a traditional lead-tin solder joint. In order to improve the impact property of SnAgCu lead-free solder joints and identify the effect of silver content on tensile strength and impact property, impact experiments were conducted at various strain rates on three selected SnAgCu based solder joints. It was found that joint failure mainly occurred in the solder material with large plastic deformation under low strain rate, while joint failure occurred at the brittle intermetallic compound layer without any plastic deformation at a high strain rate. Joint strength increased with the silver content in SnAgCu alloys in static tensile tests, while the impact property of the solder joint decreased with increasing silver content. When the strain rate was low, plastic deformation occurred with failure and the tensile strength of the Sn-3.0Ag-0.5Cu solder joint was higher than that of Sn-0.3Ag-0.7Cu; when the strain rate was high, joint failure mainly occurred at the brittle interface layer and the Sn-0.3Ag-0.7Cu solder joint had a better impact resistance with a thinner intermetallic compound layer.

  4. The Joint Master Operational Planner

    DTIC Science & Technology

    2016-04-04

    Daniel H. Hibner, United States Army Joint Forces Staff College Joint Advanced Warfighting School 7800 Hampton Blvd. Norfolk, VA 23511-1702 Approved...Operational Art. Unclass Unclass Unclass Unclassified Unlimited 66 757-443-6301 NATIONAL DEFENSE UNIVERSITY JOINT FORCES STAFF COLLEGE JOINT ADVANCED...of this paper reflect my own personal views and are not necessarily endorsed by the Joint Forces Staff College or the department of Defense. Thesis

  5. Joint attention revisited: Finding strengths among children with autism.

    PubMed

    Hurwitz, Sarah; Watson, Linda R

    2016-07-01

    Differences in joint attention are prominent for some children with autism and are often used as an indicator of the disorder. This study examined the joint attention competencies of young children with autism who demonstrated joint attention ability and compared them to children with developmental delays. A total of 40 children with autism and developmental delays were matched pairwise based on mental and chronological age. Videos of children engaging in play were coded for the frequency and forms (eye contact, gestures, affect, etc.) of joint attention. Additionally, concurrent language was compared among children with autism (N = 32) by their joint attention ability. Children with autism spectrum disorder entered into joint attention significantly less often than children with developmental delays, but once engaged used the forms of joint attention similarly. For the matched pairs, there were no differences in language, but the children with autism who used joint attention had significantly better language than children with autism who did not (even after controlling for mental age). There is a group of young children with autism who can use joint attention but do so at lower frequencies than children with developmental delays. Possible reasons include difficulty disengaging attention and limited intrinsic social motivation to share. Adult persistence is recommended to encourage joint attention. © The Author(s) 2015.

  6. Cellular Pressure-Actuated Joint

    NASA Technical Reports Server (NTRS)

    McGuire, John R.

    2003-01-01

    A modification of a pressure-actuated joint has been proposed to improve its pressure actuation in such a manner as to reduce the potential for leakage of the pressurizing fluid. The specific joint for which the modification is proposed is a field joint in a reusable solid-fuel rocket motor (RSRM), in which the pressurizing fluid is a mixture of hot combustion gases. The proposed modification could also be applicable to other pressure-actuated joints of similar configuration.

  7. Mechanics of Suture Joints

    NASA Astrophysics Data System (ADS)

    Li, Yaning; Song, Juha; Ortiz, Christine; Boyce, Mary; Ortiz Group/DMSE/MIT Team; Boyce Group/ME/MIT Team

    2011-03-01

    Biological sutures are joints which connect two stiff skeletal or skeletal-like components. These joints possess a wavy geometry with a thin organic layer providing adhesion. Examples of biological sutures include mammalian skulls, the pelvic assembly of the armored fish Gasterosteus aculeatus (the three-spined stickleback), and the suture joints in the shell of the red-eared slider turtle. Biological sutures allow for movement and compliance, control stress concentrations, transmit loads, reduce fatigue stress and absorb energy. In this investigation, the mechanics of the role of suture geometry in providing a naturally optimized joint is explored. In particular, analytical and numerical micromechanical models of the suture joint are constructed. The anisotropic mechanical stiffness and strength are studied as a function of suture wavelength, amplitude and the material properties of the skeletal and organic components, revealing key insights into the optimized nature of these ubiquitous natural joints.

  8. The Influence of Joint Distraction Force on the Soft-Tissue Balance Using Modified Gap-Balancing Technique in Posterior-Stabilized Total Knee Arthroplasty.

    PubMed

    Nagai, Kanto; Muratsu, Hirotsugu; Takeoka, Yoshiki; Tsubosaka, Masanori; Kuroda, Ryosuke; Matsumoto, Tomoyuki

    2017-10-01

    During modified gap-balancing technique, there is no consensus on the best method for obtaining appropriate soft-tissue balance and determining the femoral component rotation. Sixty-five varus osteoarthritic patients underwent primary posterior-stabilized total knee arthroplasty using modified gap-balancing technique. The influence of joint distraction force on the soft-tissue balance measurement during the modified gap-balancing technique was evaluated with Offset Repo-Tensor between the osteotomized surfaces at extension, and between femoral posterior condyles and tibial osteotomized surface at flexion of the knee before the resection of femoral posterior condyles. The joint center gap (millimeters) and varus ligament balance (°) were measured under 20, 40, and 60 pounds of joint distraction forces, and the differences in these values at extension and flexion (the value at flexion minus the value at extension) were also calculated. The differences in joint center gap (-6.7, -6.8, and -6.9 mm for 20, 40, and 60 pounds, respectively) and varus ligament balance (3.5°, 3.8°, and 3.8°) at extension and flexion were not significantly different among different joint distraction forces, although the joint center gap and varus ligament balance significantly increased stepwise at extension and flexion as the joint distraction force increased. The difference in joint center gap and varus ligament balance at extension and flexion were consistent even among the different joint distraction forces. This novel index would be useful for the determination of femoral component rotation during the modified gap-balancing technique. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. The Interface of Mechanics and Nociception in Joint Pathophysiology: Insights From the Facet and Temporomandibular Joints

    PubMed Central

    Sperry, Megan M.; Ita, Meagan E.; Kartha, Sonia; Zhang, Sijia; Yu, Ya-Hsin; Winkelstein, Beth

    2017-01-01

    Chronic joint pain is a widespread problem that frequently occurs with aging and trauma. Pain occurs most often in synovial joints, the body's load bearing joints. The mechanical and molecular mechanisms contributing to synovial joint pain are reviewed using two examples, the cervical spinal facet joints and the temporomandibular joint (TMJ). Although much work has focused on the macroscale mechanics of joints in health and disease, the combined influence of tissue mechanics, molecular processes, and nociception in joint pain has only recently become a focus. Trauma and repeated loading can induce structural and biochemical changes in joints, altering their microenvironment and modifying the biomechanics of their constitutive tissues, which themselves are innervated. Peripheral pain sensors can become activated in response to changes in the joint microenvironment and relay pain signals to the spinal cord and brain where pain is processed and perceived. In some cases, pain circuitry is permanently changed, which may be a potential mechanism for sustained joint pain. However, it is most likely that alterations in both the joint microenvironment and the central nervous system (CNS) contribute to chronic pain. As such, the challenge of treating joint pain and degeneration is temporally and spatially complicated. This review summarizes anatomy, physiology, and pathophysiology of these joints and the sensory pain relays. Pain pathways are postulated to be sensitized by many factors, including degeneration and biochemical priming, with effects on thresholds for mechanical injury and/or dysfunction. Initiators of joint pain are discussed in the context of clinical challenges including the diagnosis and treatment of pain. PMID:28056123

  10. [Arthroscopic therapy of ankle joint impingement syndrome after operation of ankle joint fracture dislocation].

    PubMed

    Feng, Zhibin; Mi, Kun; Wei, Renzhi; Liu, Wu; Wang, Bin

    2011-07-01

    To study the operative procedure and the effectiveness of arthroscopic therapy for ankle joint impingement syndrome after operation of ankle joint fracture dislocation. Between March 2008 and April 2010, 38 patients with ankle joint impingement syndrome after operation of ankle joint fracture dislocation were treated. Among them, there were 28 males and 10 females with an average age of 28 years (range, 18 to 42 years). The time from internal fixation to admission was 12-16 months (mean, 13.8 months). There were pressing pain in anterolateral and anterior ankle. The dorsal extension ranged from -20 to -5 degrees (mean, -10.6 degrees), and the palmar flexion was 30-40 degrees (mean, 35.5 degrees). The total score was 48.32 +/- 9.24 and the pain score was 7.26 +/- 1.22 before operation according to American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot score system. The X-ray films showed osteophyte formation in anterior tibia and talus; MRI showed cartilage injury in 22 cases. Arthroscopic intervention included removing osteophytes, debriding fabric scars and synovial membrane tissues, and removing osteochondral fragments. Arthroscopic microfracture technique was used in 22 patients with cartilage injury. All incisions healed primarily. Thirty-eight cases were followed up 10-26 months (mean, 16 months). At last follow-up, 26 patients had normal range of motion (ROM); the dorsal extension was 15-25 degrees (mean, 19.6 degrees) and the palmar flexion was 35-45 degrees (mean, 40.7 degrees). Eight patients had mild limited ROM; the dorsal extension was 5-15 degrees (mean, 7.2 degrees) and the palmar flexion was 35-45 degrees (mean, 39.5 degrees). Four patients had mild limited ROM and pain in posterior portion of the ankle after a long walking (3-4 hours); the dorsal extension was 0-5 degrees (mean, 2.6 degrees) and the palmar flexion was 35-40 degrees (mean, 37.5 degrees). The total score was 89.45 +/- 9.55 and the pain score was 1.42 +/- 1.26 after

  11. Joint Enrollment Report, 2014

    ERIC Educational Resources Information Center

    Iowa Department of Education, 2014

    2014-01-01

    The Iowa Department of Education collects information on joint enrollment in Iowa's 15 community colleges. Jointly enrolled students are high school students enrolled in community college credit coursework. Most jointly enrolled students enroll through Senior Year Plus (SYP) programs such as Postsecondary Enrollment Options (PSEO) and concurrent…

  12. Joint Enrollment Report, 2015

    ERIC Educational Resources Information Center

    Iowa Department of Education, 2015

    2015-01-01

    The Iowa Department of Education collects information on joint enrollment from Iowa's 15 community colleges. Jointly enrolled students are high school students enrolled in community college credit coursework. Most jointly enrolled students enroll through Senior Year Plus programs such as Postsecondary Enrollment Options (PSEO) and concurrent…

  13. Migrating lumbar facet joint cysts.

    PubMed

    Palmieri, Francesco; Cassar-Pullicino, Victor N; Lalam, Radhesh K; Tins, Bernhard J; Tyrrell, Prudencia N M; McCall, Iain W

    2006-04-01

    The majority of lumbar facet joint cysts (LFJCs) are located in the spinal canal, on the medial aspect of the facet joint with characteristic diagnostic features. When they migrate away from the joint of origin, they cause diagnostic problems. In a 7-year period we examined by computed tomography (CT) and magnetic resonance (MR) imaging five unusual cases of facet joint cysts which migrated from the facet joint of origin. Three LFJCs were identified in the right S1 foramen, one in the right L5-S1 neural foramen and one in the left erector spinae and multifidus muscles between the levels of L2-L4 spinous process. Awareness that spinal lesions identified at MRI and CT could be due to migrating facet joint cyst requires a high level of suspicion. The identification of the appositional contact of the cyst and the facet joint needs to be actively sought in the presence of degenerative facet joints.

  14. Joint Chiefs of Staff > Directorates > J7 | Joint Force Development

    Science.gov Websites

    development: Doctrine, Education, Concept Development & Experimentation, Training, Exercises and Lessons Coalition Partners. Joint Education Develop policies governing officer and enlisted Joint Professional Military Education (JPME), and the National Defense University. Direct JPME educational advisory group and

  15. Effects of joints in truss structures

    NASA Technical Reports Server (NTRS)

    Ikegami, R.

    1988-01-01

    The response of truss-type structures for future space applications, such as Large Deployable Reflector (LDR), will be directly affected by joint performance. Some of the objectives of research at BAC were to characterize structural joints, establish analytical approaches that incorporate joint characteristics, and experimentally establish the validity of the analytical approaches. The test approach to characterize joints for both erectable and deployable-type structures was based upon a Force State Mapping Technique. The approach pictorially shows how the nonlinear joint results can be used for equivalent linear analysis. Testing of the Space Station joints developed at LaRC (a hinged joint at 2 Hz and a clevis joint at 2 Hz) successfully revealed the nonlinear characteristics of the joints. The Space Station joints were effectively linear when loaded to plus or minus 500 pounds with a corresponding displacement of about plus or minus 0.0015 inch. It was indicated that good linear joints exist which are compatible with errected structures, but that difficulty may be encountered if nonlinear-type joints are incorporated in the structure.

  16. Reoperations following proximal interphalangeal joint nonconstrained arthroplasties.

    PubMed

    Pritsch, Tamir; Rizzo, Marco

    2011-09-01

    To retrospectively analyze the reasons for reoperations following primary nonconstrained proximal interphalangeal (PIP) joint arthroplasty and review clinical outcomes in this group of patients with 1 or more reoperations. Between 2001 and 2009, 294 nonconstrained (203 pyrocarbon and 91 metal-plastic) PIP joint replacements were performed in our institution. A total of 76 fingers (59 patients) required reoperation (50 pyrocarbon and 26 metal-plastic). There were 40 women and 19 men with an average age of 51 years (range, 19-83 y). Primary diagnoses included osteoarthritis in 35, posttraumatic arthritis in 24, and inflammatory arthritis in 17 patients. There were 21 index, 27 middle, 18 ring, and 10 small fingers. The average number of reoperations per PIP joint was 1.6 (range, 1-4). A total of 45 joints had 1 reoperation, 19 had 2, 11 had 3, and 1 had 4. Extensor mechanism dysfunction was the most common reason for reoperation; it involved 51 of 76 fingers and was associated with Chamay or tendon-reflecting surgical approaches. Additional etiologies included component loosening in 17, collateral ligament failure in 10, and volar plate contracture in 8 cases. Inflammatory arthritis was associated with collateral ligament failure. Six fingers were eventually amputated, 9 had PIP joint arthrodeses, and 2 had resection arthroplasties. The arthrodesis and amputation rates correlated with the increased number of reoperations per finger. Clinically, most patients had no or mild pain at the most recent follow-up, and the PIP joint range-of-motion was not significantly different from preoperative values. Pain levels improved with longer follow-up. Reoperations following primary nonconstrained PIP joint arthroplasties are common. Extensor mechanism dysfunction was the most common reason for reoperation. The average reoperation rate was 1.6, and arthrodesis and amputation are associated with an increasing number of operations. Overall clinical outcomes demonstrated no

  17. Culture - joint fluid

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003742.htm Culture - joint fluid To use the sharing features on this page, please enable JavaScript. Joint fluid culture is a laboratory test to detect infection-causing ...

  18. Joint Chiefs of Staff > About > Joint Staff Inspector General

    Science.gov Websites

    DD Form 2949, Joint Inspector General Action Request (available at the link below). However, if you action if you intentionally make false statements. When you sign a DD Form 2949, you are signing a . DD Form 2949, Joint Inspector General Action Request Click here to expand content Click here to

  19. Patient Perception of Value in Bundled Payments for Total Joint Arthroplasty.

    PubMed

    Schwartz, Adam J; Fraser, James F; Shannon, Allison M; Jackson, Nikki T; Raghu, T S

    2016-12-01

    A central concern for providers in a bundled payment model is determining how the bundle is distributed. Prior studies have shown that current reimbursement rates are often not aligned with patients' values. While willingness-to-pay (WTP) surveys are perhaps useful in a fee-for-service arrangement to determine overall reimbursement, the percentage of payment distribution might be as or more important in a bundled payment model. All patients undergoing primary total joint arthroplasty by a single surgeon were offered participation in a preoperative WTP survey. At a minimum 3 months postoperatively, patients were mailed instructions for an online follow-up survey asking how they would allocate a hypothetical bonus payment. From January through December 2014, 45 patients agreed to participate in the preoperative WTP survey. Twenty patients who were minimum 3 months postoperative also completed the follow-up survey. Patients valued total knee and hip arthroplasty at $28,438 (95% confidence interval [CI]: $20,551-36,324) and $39,479 (95% CI: $27,848-$51,112), respectively. At 3 months postoperatively, patients distributed a hypothetical bonus payment 55.5% to the surgeon (95% CI: 47.8%-63.1%), 38% to the hospital (95% CI: 30.3%-45.7%), and 6.5% (95% CI: -1.2% to 14.2%) to the implant manufacturer (P < .001). The data suggest that total joint arthroplasty patients have vastly different perceptions of payment distributions than what actually exists. In contrast to the findings of this study, the true distribution of payments for an episode of care averages 65% to the hospital, 27% to the implant manufacturer, and 8% to the surgeon. While many drivers of payment distribution exist, this study suggests that patients would allocate a larger proportion of a bundled payment to surgeons than is currently disbursed. This finding may also provide a plausible explanation for patients' consistent overestimation of surgeon reimbursements. Copyright © 2016 Elsevier Inc. All rights

  20. Ceramic joints

    DOEpatents

    Miller, Bradley J.; Patten, Jr., Donald O.

    1991-01-01

    Butt joints between materials having different coefficients of thermal expansion are prepared having a reduced probability of failure of stress facture. This is accomplished by narrowing/tapering the material having the lower coefficient of thermal expansion in a direction away from the joint interface and not joining the narrow-tapered surface to the material having the higher coefficient of thermal expansion.

  1. Sacroiliac joint dysfunction.

    PubMed

    Ilaslan, Hakan; Arslan, Ahmet; Koç, Omer Nadir; Dalkiliç, Turker; Naderi, Sait

    2010-07-01

    Sacroiliac joint dysfunction is a disorder presenting with low back and groin pain. It should be taken into consideration during the preoperative differential diagnosis of lumbar disc herniation, lumbar spinal stenosis and facet syndrome. Four cases with sacroiliac dysfunction are presented. The clinical and radiological signs supported the evidence of sacroiliac dysfunction, and exact diagnosis was made after positive response to sacroiliac joint block. A percutaneous sacroiliac fixation provided pain relief in all cases. The mean VAS scores reduced from 8.2 to 2.2. It is concluded that sacroiliac joint dysfunction diagnosis requires a careful physical examination of the sacroiliac joints in all cases with low back and groin pain. The diagnosis is made based on positive response to the sacroiliac block. Sacroiliac fixation was found to be effective in carefully selected cases.

  2. Hip joint injection

    MedlinePlus

    ... medicine into the joint. The provider uses a real-time x-ray (fluoroscopy) to see where to place ... Wakefield RJ. Arthrocentesis and injection of joints and soft tissue. In: Firestein GS, Budd RC, Gabriel SE, ...

  3. [Generalised Form of Synovial Chondromatosis of the Knee Joint].

    PubMed

    Vališ, P; Vyskočil, R

    2016-01-01

    This study describes a diagnostic and therapeutic algorithm in a 53-year-old male patient who was diagnosed with a synovial chondromatosis of the knee joint extending to the popliteal fossa and soft tissues around the knee. Because of the presence of massive nodules, the patient was indicated for total synovectomy, with removal of pathologically changed cartilaginous tissue, performed by combined anterior and posterior approaches to the knee joint. Despite complete removal of the synovium and loose cartilage bodies and the patient's pain relief in the post-operative time, three years after the operation new problems appeared. Magnetic resonance imaging (MRI) confirmed a relapse of synovial chondromatosis and the patient was indicated for revision surgery of the knee joint. The results of physical examination and MRI scans, and intra-operative findings in the patient are reported. synovial chondromatosis, total synovectomy, direct anterior and posterior approaches to the knee joint.

  4. Comparative study of the detection of joint injury in early-stage rheumatoid arthritis by magnetic resonance imaging of the wrist and finger joints and physical examination.

    PubMed

    Tamai, Mami; Kawakami, Atsushi; Iwamoto, Naoki; Kawashiri, Shin-Ya; Fujikawa, Keita; Aramaki, Toshiyuki; Kita, Junko; Okada, Akitomo; Koga, Tomohiro; Arima, Kazuhiko; Kamachi, Makoto; Yamasaki, Satoshi; Nakamura, Hideki; Ida, Hiroaki; Origuchi, Tomoki; Takao, Shoichiro; Aoyagi, Kiyoshi; Uetani, Masataka; Eguchi, Katsumi

    2011-03-01

    To verify whether magnetic resonance imaging (MRI)-proven joint injury is sensitive as compared with joint injury determined by physical examination. MRI of the wrist and finger joints of both hands was examined in 51 early-stage rheumatoid arthritis (RA) patients by both plain and gadolinium diethylenetriaminepentaacetic acid-enhanced MRI. Synovitis, bone edema, and bone erosion (the latter two included as bone lesions at the wrist joints); metacarpophalangeal joints; and proximal interphalangeal joints were considered as MRI-proven joint injury. Japan College of Rheumatology-certified rheumatologists had given a physical examination just before the MRI study. The presence of tender and/or swollen joints in the same fields as MRI was considered as joint injury on physical examination. The association of MRI-proven joint injury with physical examination-proven joint injury was examined. A total of 1,110 sites were available to be examined. MRI-proven joint injury was found in 521 sites, whereas the other 589 sites were normal. Physical examination-proven joint injury was found in 305 sites, which was significantly low as compared with MRI-proven joint injury (P = 1.1 × 10(-12) versus MRI). Joint injury on physical examination was not found in 81.5% of the sites where MRI findings were normal. Furthermore, an association of the severity of MRI-proven joint injury with that of joint injury on physical examination was clearly demonstrated (P = 1.6 × 10(-15), r(s) = 0.469). Our present data suggest that MRI is not only sensitive but accurately reflects the joint injury in patients with early-stage RA. Copyright © 2011 by the American College of Rheumatology.

  5. Blood, bugs, and motion - what do we really know in regard to total joint arthroplasty?

    PubMed

    Glassner, Philip J; Slover, James D; Bosco, Joseph A; Zuckerman, Joseph D

    2011-01-01

    In total joint arthroplasty, it is often necessary to formulate decisions that are not clearly evidence-based. This review presents some current controversial topics in total joint arthroplasty, including preoperative autologous blood donation versus erythropoietin (EPO) usage, preoperative screening and treatment for methicillin resistant Staphylococcus aureus (MRSA), and the use of continuous passive motion (CPM) following total knee arthroplasty, providing an evidence-based guide for the treating orthopaedic surgeon. Our review shows that preoperative autologous blood donation is over utilized, with EPO being under utilized. Surgeons are encouraged to develop patient-specific strategies, which have been shown to decrease transfusion rates, reduce wasted autologous blood, and increase EPO use. Definitive conclusions regarding MRSA screening for orthopaedic patients cannot be drawn; but due to the significant cost and morbidity associated with a postoperative MRSA infection, we believe a screen and treat protocol should be considered for all patients being admitted to the hospital for elective or emergent surgery. Short-term (3 to 5 days) inpatient use of CPM is recommended at this time. It is low-cost, has minimal risk, and may be a factor in decreasing the length of stay, potentially leading to significant cost savings. However, no long-term benefits of CPM use have been established.

  6. Multidisciplinary patient education for total joint replacement surgery patients.

    PubMed

    Prouty, Anne; Cooper, Maureen; Thomas, Patricia; Christensen, Judy; Strong, Cheryl; Bowie, Lori; Oermann, Marilyn H

    2006-01-01

    The purpose of this article is to describe a preadmission, preoperative educational program offered free of charge for patients undergoing total joint replacement surgery at a large teaching hospital located in metropolitan Detroit, Michigan. In establishing the preoperative educational program, a multidisciplinary approach was used to provide a comprehensive learning environment for patients and their families. To evaluate the effectiveness of the program, patients completed surveys at the end of each class. Patients reported that their expectations of the program were met, they were less anxious about their surgery as a result of attending the classes, and the preoperative teaching by the multidisciplinary team was effective. Having a live session that offered an opportunity to ask individual and specific questions to each healthcare professional with immediate feedback proved to be a positive experience for patients. Patients' comments supported the multidisciplinary team's impression that real-time, interactive teaching was highly valued by patients and their caregivers.

  7. Postoperative Complications of Total Joint Arthroplasty in Obese Patients Stratified by BMI.

    PubMed

    Zusmanovich, Mikhail; Kester, Benjamin S; Schwarzkopf, Ran

    2018-03-01

    High body mass index (BMI) is associated with significant complications in patients undergoing total joint arthroplasty. Many studies have evaluated this trend, but few have looked at the rates of complications based on BMI as a continuous variable. The purpose of this study was to stratify obese patients into 3 BMI categories and evaluate their rates of complications and gauge whether transitioning from higher to lower BMI category lowers complication. Patients undergoing primary total joint arthroplasty were selected from the National Surgical Quality Improvement Program database from 2008-2015 and arranged into 3 groups based on BMI: O1 (BMI 30-34.9 kg/m 2 ), O2 (BMI 35-39.9 kg/m 2 ), and O3 (BMI >40 kg/m 2 ). Thirty-day complications were recorded and evaluated utilizing univariate and multivariate analyses stratified by BMI. A total of 268,663 patients were identified. Patients with a BMI >30 kg/m 2 had more infectious and medical complications compared with nonobese patients. Furthermore, there were increased complications as the BMI categories increased. Patients with a BMI >40 kg/m 2 (O3) had longer operating times, length of stay, higher rates of readmissions, reoperations, deep venous thrombosis, renal insufficiency, superficial infections, deep infections, and wound dehiscence. These trends were present when comparing the O2 with O1 category as well. We have demonstrated increased rates of medical and surgical complications in obese patients. Furthermore, we demonstrated a stepwise increase in complication rates when transitioning to higher BMI groups. Based on our data, we believe that preoperative counseling and interventions to decrease BMI should be explored before offering elective surgery to obese patients. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Joint Aspiration (Arthrocentesis)

    MedlinePlus

    ... arthritis, or JRA), systemic lupus erythematosus (SLE), and Lyme disease. Joint aspiration is diagnostic but it also can ... topic for: Parents Kids Teens Evaluate Your Child's Lyme Disease Risk Living With Lupus Bones, Muscles, and Joints ...

  9. Longitudinal joint study.

    DOT National Transportation Integrated Search

    2001-09-01

    In previous years there has been a problem with longitudinal joint : deterioration, due in part to poor construction techniques. : The degradation of the longitudinal joints has increased the cost of : maintaining these projects and caused unnecessar...

  10. Sports activity after total joint arthroplasty: recommendations for the counseling physician.

    PubMed

    Buza, John A; Fink, Leslie A; Levine, William N

    2013-02-01

    Sports activity after total joint arthroplasty (TJA) has become an increasingly important topic, as many younger patients seeking TJA have higher postoperative expectations with regard to return to athletic activity. Our current knowledge of this area is largely based on retrospective clinical studies and surveys of surgeon recommendations. The decision to participate in sports after TJA depends on the patient's general health, prior athletic experience, type of TJA, and desired sporting activity. Ultimately, patients should discuss these factors with their physician in order to make an educated decision regarding sports activity after TJA. This article summarizes the best available evidence to help guide physicians in their conversation with patients regarding safe and appropriate sports activity after TJA.

  11. Joint Control for Dummies: An Elaboration of Lowenkron's Model of Joint (Stimulus) Control

    ERIC Educational Resources Information Center

    Sidener, David W.

    2006-01-01

    The following paper describes Lowenkron's model of joint (stimulus) control. Joint control is described as a means of accounting for performances, especially generalized performances, for which a history of contingency control does not provide an adequate account. Examples are provided to illustrate instances in which joint control may facilitate…

  12. The association of sacroiliac joint bridging with other enthesopathies in the human body.

    PubMed

    Dar, Gali; Peleg, Smadar; Masharawi, Youssef; Steinberg, Nili; Rothschild, Bruce M; Hershkovitz, Israel

    2007-05-01

    A descriptive study of the association between sacroiliac joint (extra-articular) bridging and other enthesopathies. To examine the relationship between sacroiliac joint bridging with other entheseal reaction sites in the skeleton, and its prognostic value in spinal diseases. Sacroiliac joint bridging is considered a hallmark of spinal diseases (e.g., ankylosing spondylitis). Nevertheless, its association with other enthesopathies has never been quantified and analyzed. A total of 289 human male skeletons with sacroiliac joint bridging and 127 without (of similar demographic structure) were evaluated for the presence of entheseal ossification, cartilaginous calcification, and other axial skeleton joint fusion (a total of 18 anatomic sites). The presence of diffuse idiopathic skeletal hyperostosis and spondyloarthropathy was also recorded. Sacroiliac joint bridging was strongly associated with entheseal reactions in other parts of the body. Of the sacroiliac joint bridging group, 24.91% had diffuse idiopathic skeletal hyperostosis, and 8.05% had spondyloarthropathy. The presence of sacroiliac joint bridging indicates an intensive general entheseal process in the skeleton.

  13. Total knee arthroplasty for the management of joint destruction in tuberculous arthritis.

    PubMed

    Oztürkmen, Yusuf; Uzümcügil, Onat; Karamehmetoğlu, Mahmut; Leblebici, Cem; Caniklioğlu, Mustafa

    2014-05-01

    The purpose of this study was to evaluate our experience to clarify the suggestion that there should be a significant disease-free interval before total knee arthroplasty (TKA) and to determine the correct timing of surgery for reconstruction of the joint destruction in patients suffering from tuberculous arthritis. Twelve patients with advanced joint destruction and tuberculous arthritis of the knee with recent onset were reviewed in this study. The time interval from our diagnosis of active infection to arthroplasty averaged 4 ± 1.5 months. Histopathology of the biopsy specimens revealing granulomatous lesions, including epithelioid histiocytes surrounded by lymphocytes, confirmed the diagnosis of each patient. A primary knee prosthesis was performed in seven knees. In five knees, there was severe bone loss after the extensive debridement of the entire joint, and thereafter, revision prosthesis was preferred to preserve the joint line. Patients were given post-operative antituberculous treatment for a total of 1 year, whereas for three patients, whose erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) values remained above normal by the sixth month, the chemotherapy was continued for up to 18 months. The Knee Society TKA roentgenographic evaluation and scoring system was used for radiological evaluation of the knees. Clinical evaluation of the knees was done preoperatively and at the time of the most recent follow-up using the American Knee Society Scoring System. Within the average follow-up period of 6.1 ± 1.8 years, no reactivation of tuberculous infection was found in any of the patients. ESR was normal, less than 20 mm/h, after a mean time of 5.5 ± 2.0 months. The CRP was normal, less than 0.8 mg/dl, after a mean time of 4.6 ± 1.3 months. At the most recent follow-up, the average knee score improved from 32.4 ± 19.4 to 83.4 ± 14.0 points (p < 0.05), and the average function score improved from 33.3 ± 11.9 to 86

  14. "Combined Diagnostic Tool" APPlication to a Retrospective Series of Patients Undergoing Total Joint Revision Surgery.

    PubMed

    Gallazzi, Enrico; Drago, Lorenzo; Baldini, Andrea; Stockley, Ian; George, David A; Scarponi, Sara; Romanò, Carlo L

    2017-01-01

    Background : Differentiating between septic and aseptic joint prosthesis may be challenging, since no single test is able to confirm or rule out infection. The choice and interpretation of the panel of tests performed in any case often relies on empirical evaluation and poorly validated scores. The "Combined Diagnostic Tool (CDT)" App, a smartphone application for iOS, was developed to allow to automatically calculate the probability of having a of periprosthetic joint infection, on the basis of the relative sensitivity and specificity of the positive and negative diagnostic tests performed in any given patient. Objective : The aim of the present study was to apply the CDT software to investigate the ability of the tests routinely performed in three high-volume European centers to diagnose a periprosthetic infection. Methods : This three-center retrospective study included 120 consecutive patients undergoing total hip or knee revision, and included 65 infected patients (Group A) and 55 patients without infection (Group B). The following parameters were evaluated: number and type of positive and negative diagnostic tests performed pre-, intra- and post-operatively and resultant probability calculated by the CDT App of having a peri-prosthetic joint infection, based on pre-, intra- and post-operative combined tests. Results : Serological tests were the most common performed, with an average 2.7 tests per patient for Group A and 2.2 for Group B, followed by joint aspiration (0.9 and 0.8 tests per patient, respectively) and imaging techniques (0.5 and 0.2 test per patient). Mean CDT App calculated probability of having an infection based on pre-operative tests was 79.4% for patients in Group A and 35.7 in Group B. Twenty-nine patients in Group A had > 10% chance of not having an infection, and 29 of Group B had > 10% chance of having an infection. Conclusion : This is the first retrospective study focused on investigating the number and type of tests commonly performed

  15. Is latero-medial patellar mobility related to the range of motion of the knee joint after total knee arthroplasty?

    PubMed

    Ota, Susumu; Nakashima, Takeshi; Morisaka, Ayako; Omachi, Takaaki; Ida, Kunio; Kawamura, Morio

    2010-12-01

    Diminished range of motion (ROM) of the knee joint after total knee arthroplasty (TKA) is thought to be related to reduced patellar mobility. This has not been confirmed clinically due to a lack of quantitative methods adequate for measuring patellar mobility. We investigated the relationship between patellar mobility by a reported quantitative method and knee joint ROM after TKA. Forty-nine patients [osteoarthritis--OA: 29 knees; rheumatoid arthritis--RA: 20 knees] were examined after TKA. Respective medial and lateral patellar mobility was measured 1 and 6 months postoperatively using a patellofemoral arthrometer (PFA). Knee joint ROM was also measured in each of those 2 sessions. Although the flexion and extension of the knee joints improved significantly from 1 to 6 months after TKA, the medial and lateral patellar displacements (LPDs) failed to improve during that same period. Moreover, only the changes in knee flexion and medial patellar displacement (MPD) between the two sessions were positively correlated (r = 0.31, p < 0.05). However, our findings demonstrated that medial and lateral patellar mobility had no sufficient longitudinal relationship with knee ROM after TKA. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. High pressure ceramic joint

    DOEpatents

    Ward, Michael E.; Harkins, Bruce D.

    1993-01-01

    Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present joint when used with recuperators increases the use of ceramic components which do not react to highly corrosive gases. Thus, the present joint used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present joint is comprised of a first ceramic member, a second ceramic member, a mechanical locking device having a groove defined in one of the first ceramic member and the second ceramic member. The joint and the mechanical locking device is further comprised of a refractory material disposed in the groove and contacting the first ceramic member and the second ceramic member. The present joint mechanically provides a high strength load bearing joint having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

  17. Joint Implications for Contracted Logistics

    DTIC Science & Technology

    2007-03-30

    authority with the host nation country and policy on using UCMJ for contracted personnel. As tailored theater policies are developed and contracting...responsibility, this paper recommends better joint training, leader development and joint enablers for contracting operations. JOINT...U.S. Joint Forces Command (JFCOM) are analyzing Congressional and DOD policy to develop procedures and force structure to support contractor

  18. Comparison of the use of notched wedge joints vs. traditional butt joints in Connecticut

    DOT National Transportation Integrated Search

    2008-11-07

    Performance of Hot Mix Asphalt (HMA) longitudinal joints have been an item of increasing scrutiny in : Connecticut. The traditional butt joint has typically been the method used in Connecticut. These joints : have been reportedly opening up, creating...

  19. Evaluation of narrow transverse contraction joints in jointed plain concrete pavements.

    DOT National Transportation Integrated Search

    2006-03-01

    This report presents the results of a research project conducted at the Louisiana Transportation Research Center (LTRC) to evaluate the performance of narrow transverse contraction joints to control cracking in jointed plain concrete pavements. In ad...

  20. Dichotomous versus semi-quantitative scoring of ultrasound joint inflammation in rheumatoid arthritis using novel individualized joint selection methods.

    PubMed

    Tan, York Kiat; Allen, John C; Lye, Weng Kit; Conaghan, Philip G; Chew, Li-Ching; Thumboo, Julian

    2017-05-01

    The aim of the study is to compare the responsiveness of two joint inflammation scoring systems (dichotomous scoring (DS) versus semi-quantitative scoring (SQS)) using novel individualized ultrasound joint selection methods and existing ultrasound joint selection methods. Responsiveness measured by the standardized response means (SRMs) using the DS and the SQS system (for both the novel and existing ultrasound joint selection methods) was derived using the baseline and the 3-month total inflammatory scores from 20 rheumatoid arthritis patients. The relative SRM gain ratios (SRM-Gains) for both scoring system (DS and SQS) comparing the novel to the existing methods were computed. Both scoring systems (DS and SQS) demonstrated substantial SRM-Gains (ranged from 3.31 to 5.67 for the DS system and ranged from 1.82 to 3.26 for the SQS system). The SRMs using the novel methods ranged from 0.94 to 1.36 for the DS system and ranged from 0.89 to 1.11 for the SQS system. The SRMs using the existing methods ranged from 0.24 to 0.32 for the DS system and ranged from 0.34 to 0.49 for the SQS system. The DS system appears to achieve high responsiveness comparable to SQS for the novel individualized ultrasound joint selection methods.

  1. Experimental Investigation of Composite Pressure Vessel Performance and Joint Stiffness for Pyramid and Inverted Pyramid Joints

    NASA Technical Reports Server (NTRS)

    Verhage, Joseph M.; Bower, Mark V.; Gilbert, Paul A. (Technical Monitor)

    2001-01-01

    The focus of this study is on the suitability in the application of classical laminate theory analysis tools for filament wound pressure vessels with adhesive laminated joints in particular: pressure vessel wall performance, joint stiffness and failure prediction. Two 18-inch diameter 12-ply filament wound pressure vessels were fabricated. One vessel was fabricated with a 24-ply pyramid laminated adhesive double strap butt joint. The second vessel was fabricated with the same number of plies in an inverted pyramid joint. Results from hydrostatic tests are presented. Experimental results were used as input to the computer programs GENLAM and Laminate, and the output compared to test. By using the axial stress resultant, the classical laminate theory results show a correlation within 1% to the experimental results in predicting the pressure vessel wall pressure performance. The prediction of joint stiffness for the two adhesive joints in the axial direction is within 1% of the experimental results. The calculated hoop direction joint stress resultant is 25% less than the measured resultant for both joint configurations. A correction factor is derived and used in the joint analysis. The correction factor is derived from the hoop stress resultant from the tank wall performance investigation. The vessel with the pyramid joint is determined to have failed in the joint area at a hydrostatic pressure 33% value below predicted failure. The vessel with the inverted pyramid joint failed in the wall acreage at a hydrostatic pressure within 10% of the actual failure pressure.

  2. Longitudinal joint treatment.

    DOT National Transportation Integrated Search

    2006-03-01

    Maine highways have been showing signs of longitudinal joint failure for a number of years. In an effort : to reduce the amount of joint failures the Maine Department of Transportation (MDOT) is currently : evaluating two projects. One project is mon...

  3. Cryotherapy on postoperative rehabilitation of joint arthroplasty.

    PubMed

    Ni, Sheng-Hui; Jiang, Wen-Tong; Guo, Lei; Jin, Yu-Heng; Jiang, Tian-Long; Zhao, Yuyan; Zhao, Jie

    2015-11-01

    The effectiveness of cryotherapy on joint arthroplasty recovery remains controversial. This systematic review was conducted to assess the effectiveness of cryotherapy in patients after joint arthroplasty. Comprehensive literature searches of several databases including Cochrane Library (2013), MEDLINE (1950-2013), and Embase (1980-2013) were performed. We sought randomised controlled trials that compared the experimental group received any form of cryotherapy with any control group after joint arthroplasty. The main outcomes were postoperative blood loss, adverse events, and pain. Analyses were performed with Revman 5.0. Results were shown as mean differences (MD) and standard deviations or as risk difference and 95 % confidence intervals (CIs). Ten trials comprised 660 total knee arthroplastys and three trials comprised 122 total hip arthroplastys (THAs) met the inclusion criteria. Blood loss was significantly decreased by cryotherapy (MD = -109.68; 95 % CI -210.92 to -8.44; P = 0.03). Cryotherapy did not increase the risk of adverse effect (n.s.). Cryotherapy decreased pain at the second day of postoperative (MD = -1.32; 95 % CI -2.37 to -0.27; P = 0.0003), but did not decreased pain at the first and third day of postoperative (n.s.). Cryotherapy appears effective in these selected patients after joint arthroplasty. The benefits of cryotherapy on blood loss after joint arthroplasty were obvious. However, the subgroup analysis indicated that cryotherapy did not decreased blood loss after THA. Cryotherapy did not increase the risk of adverse effect. Cryotherapy decreased pain at the second day of postoperative, but did not decreased pain at the first and third day of postoperative. II.

  4. Novel Ultrasound Joint Selection Methods Using a Reduced Joint Number Demonstrate Inflammatory Improvement when Compared to Existing Methods and Disease Activity Score at 28 Joints.

    PubMed

    Tan, York Kiat; Allen, John C; Lye, Weng Kit; Conaghan, Philip G; D'Agostino, Maria Antonietta; Chew, Li-Ching; Thumboo, Julian

    2016-01-01

    A pilot study testing novel ultrasound (US) joint-selection methods in rheumatoid arthritis. Responsiveness of novel [individualized US (IUS) and individualized composite US (ICUS)] methods were compared with existing US methods and the Disease Activity Score at 28 joints (DAS28) for 12 patients followed for 3 months. IUS selected up to 7 and 12 most ultrasonographically inflamed joints, while ICUS additionally incorporated clinically symptomatic joints. The existing, IUS, and ICUS methods' standardized response means were -0.39, -1.08, and -1.11, respectively, for 7 joints; -0.49, -1.00, and -1.16, respectively, for 12 joints; and -0.94 for DAS28. Novel methods effectively demonstrate inflammatory improvement when compared with existing methods and DAS28.

  5. Accuracy of acromioclavicular joint injections.

    PubMed

    Wasserman, Bradley R; Pettrone, Sarah; Jazrawi, Laith M; Zuckerman, Joseph D; Rokito, Andrew S

    2013-01-01

    Injection to the acromioclavicular (AC) joint can be both diagnostic and therapeutic. The purpose of this study was to evaluate the accuracy of in vivo AC joint injections. Case series; Level of evidence, 4. Thirty patients with pain localized to the AC joint were injected with 1 mL of 1% lidocaine and 0.5 mL of radiographic contrast material (Isovue). Radiographs of the AC joint were taken after the injection. Each radiograph was reviewed by a musculoskeletal radiologist and graded as intra-articular, extra-articular, or partially intra-articular. Of the 30 injections performed, 13 (43.3%) were intra-articular, 7 (23.3%) were partially articular, and 10 (33.3%) were extra-articular. When the intra-articular and the partially articular groups were combined, 20 patients (66.7%) had some contrast dye in the AC joint. This study demonstrates that despite the relatively superficial location of the AC joint, the clinical accuracy of AC joint injections remains relatively low.

  6. Can symptomatic acromioclavicular joints be differentiated from asymptomatic acromioclavicular joints on 3-T MR imaging?

    PubMed

    Choo, Hye Jung; Lee, Sun Joo; Kim, Jung Han; Cha, Seong Sook; Park, Young Mi; Park, Ji Sung; Lee, Jun Woo; Oh, Minkyung

    2013-04-01

    To evaluate retrospectively whether symptomatic acromioclavicular joints can be differentiated from asymptomatic acromioclavicular joints on 3-T MR imaging. This study included 146 patients who underwent physical examination of acromioclavicular joints and 3-T MR imaging of the shoulder. Among them, 67 patients showing positive results on physical examination were assigned to the symptomatic group, whereas 79 showing negative results were assigned to the asymptomatic group. The following MR findings were compared between the symptomatic and asymptomatic groups: presence of osteophytes, articular surface irregularity, subchondral cysts, acromioclavicular joint fluid, subacromial fluid, subacromial bony spurs, joint capsular distension, bone edema, intraarticular enhancement, periarticular enhancement, superior and inferior joint capsular distension degree, and joint capsular thickness. The patients were subsequently divided into groups based on age (younger, older) and the method of MR arthrography (direct MR arthrography, indirect MR arthrography), and all the MR findings in each subgroup were reanalyzed. The meaningful cutoff value of each significant continuous variable was calculated using receiver operating characteristic analysis. The degree of superior capsular distension was the only significant MR finding of symptomatic acromioclavicular joints and its meaningful cutoff value was 2.1mm. After subgroup analyses, this variable was significant in the older age group and indirect MR arthrography group. On 3-T MR imaging, the degree of superior joint capsular distension might be a predictable MR finding in the diagnosis of symptomatic acromioclavicular joints. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  7. [Effects of exercise on joints.

    PubMed

    Moriyama, Hideki

    Joints are composed of several different tissues(cartilage, capsule, meniscus, and ligament), and articular cartilage plays an important role in maintaining mechanical competence during exercise. Weight-bearing exercise has several benefit, including improved blood and synovial fluid circulation in a given joint. Consistent moderate activities facilitate cycles of anabolism and catabolism. Mechanical stresses are crucial for the maintenance of the morphologic and functional integrity of articular cartilage. Healthy cartilage is exposed by hydrostatic pressure and tensile strain, when cartilage degeneration develops, abnormal cartilage is exposed by shear stress. Moderate(physiological)exercise is characterized by a range of equilibrium between matrix anabolic and catabolic processes, or anabolism beyond catabolism. Joints are susceptible to insufficient or excessive activities, leading to joint degeneration. Lack of exercise is known to induce joint contracture seen clinically as a consequence of disuse changes, and excess mechanical stresses induce joint destruction such as osteoarthritis. Joint diseases resulting from insufficient or excessive activities are new and major challenging issues with our aging population. Thus, it is highly desirable to have an effective and efficient treatment to improve and protect against these joint diseases, and thereby to solve these clearly unanswered issues.

  8. Functional disorders of the temporomandibular joints: Internal derangement of the temporomandibular joint.

    PubMed

    Chang, Chih-Ling; Wang, Ding-Han; Yang, Mu-Chen; Hsu, Wun-Eng; Hsu, Ming-Lun

    2018-04-01

    Temporomandibular joint (TMJ) is one of the most complex joints of the human body. Due to its unique movement, in terms of combination of rotation and translator movement, disc of the joint plays an important role to maintain its normal function. In order to sustain the normal function of the TMJ, disc must be kept in proper position as well as maintain normal shape in all circumstances. Once the disc is not any more in its normal position during function of the joint, disturbance of the joint can be occurred which will lead to subsequent distortion of the disc. Shape of the disc can be influenced by many factors i.e.: abnormal function or composition of the disc itself. Etiology of the internal derangement of the disc remains controversial. Multifactorial theory has been postulated in most of previous manuscripts. Disc is composed of mainly extracellular matrix. Abnormal proportion of collagen type I & III may also leads to joint hypermobility which may be also a predisposing factor of this disorder. Thus it can be recognized as local manifestation of a systemic disorder. Different treatment modalities with from conservative treatment to surgical intervention distinct success rate have been reported. Recently treatment with extracellular matrix injection becomes more and more popular to strengthen the joint itself. Since multifactorial in character, the best solution of the treatment modalities should be aimed to resolve possible etiology from different aspects. Team work may be indication to reach satisfied results. Copyright © 2018. Published by Elsevier Taiwan.

  9. Predicting the Functional Roles of Knee Joint Muscles from Internal Joint Moments.

    PubMed

    Flaxman, Teresa E; Alkjær, Tine; Simonsen, Erik B; Krogsgaard, Michael R; Benoit, Daniel L

    2017-03-01

    Knee muscles are commonly labeled as flexors or extensors and aptly stabilize the knee against sagittal plane loads. However, how these muscles stabilize the knee against adduction-abduction and rotational loads remains unclear. Our study sought 1) to classify muscle roles as they relate to joint stability by quantifying the relationship between individual muscle activation patterns and internal net joint moments in all three loading planes and 2) to determine whether these roles change with increasing force levels. A standing isometric force matching protocol required subjects to modulate ground reaction forces to elicit various combinations and magnitudes of sagittal, frontal, and transverse internal joint moments. Surface EMG measured activities of 10 lower limb muscles. Partial least squares regressions determined which internal moment(s) were significantly related to the activation of individual muscles. Rectus femoris and tensor fasciae latae were classified as moment actuators for knee extension and hip flexion. Hamstrings were classified as moment actuators for hip extension and knee flexion. Gastrocnemius and hamstring muscles were classified as specific joint stabilizers for knee rotation. Vastii were classified as general joint stabilizers because activation was independent of moment generation. Muscle roles did not change with increasing effort levels. Our findings indicate muscle activation is not dependent on anatomical orientation but perhaps on its role in maintaining knee joint stability in the frontal and transverse loading planes. This is useful for delineating the roles of biarticular knee joint muscles and could have implications in robotics, musculoskeletal modeling, sports sciences, and rehabilitation.

  10. New Joint Sealants. Criteria, Design and Materials.

    ERIC Educational Resources Information Center

    Building Research Inst., Inc., Washington, DC.

    Contents include--(1) sealing concrete joints, (2) sealing glass and metal joints, (3) metal and glass joint sealants from a fabricator's viewpoint, (4) a theory of adhesion for joint sealants, (5) geometry of simple joint seals under strain, (6) joint sealant specifications from a manufacturer's viewpoint, (7) joint sealant requirements from an…

  11. Duplex Ultrasonography Has Limited Utility in Detection of Postoperative DVT After Primary Total Joint Arthroplasty.

    PubMed

    Vira, Shaleen; Ramme, Austin J; Alaia, Michael J; Steiger, David; Vigdorchik, Jonathan M; Jaffe, Frederick

    2016-07-01

    Duplex ultrasound is routinely used to evaluate suspected deep venous thrombosis after total joint arthroplasty. When there is a clinical suspicion for a pulmonary embolism, a chest angiogram (chest CTA) is concomitantly obtained. Two questions were addressed: First, for the population of patients who receive duplex ultrasound after total joint arthroplasty, what is the rate of positive results? Second, for these patients, how many of these also undergo chest CTA for clinical suspicion of pulmonary embolus and how many of these tests are positive? Furthermore, what is the correlation between duplex ultrasound results and chest CTA results? A retrospective chart review was conducted of total joint replacement patients in 2011 at a single institution. Inclusion criteria were adult patients who underwent a postoperative duplex ultrasonography for clinical suspicion of deep venous thrombosis (DVT). Demographic data, result of duplex scan, clinical indications for obtaining the duplex scan, and DVT prophylaxis used were recorded. Additionally, if a chest CTA was obtained for clinical suspicion for pulmonary embolus, results and clinical indication for obtaining the test were recorded. The rate of positive results for duplex ultrasonography and chest CTA was computed and correlated based on clinical indications. Two hundred ninety-five patients underwent duplex ultrasonography of which only 0.7% were positive for a DVT. One hundred three patients underwent a chest CTA for clinical suspicion of a pulmonary embolism (PE) of which 26 revealed a pulmonary embolus, none of which had a positive duplex ultrasound. Postoperative duplex scans have a low rate of positive results. A substantial number of patients with negative duplex results subsequently underwent chest CTA for clinical suspicion for which a pulmonary embolus was found, presumably resulting from a DVT despite negative duplex ultrasound result. A negative duplex ultrasonography should not rule out the presence of a

  12. Anaerobic prosthetic joint infection.

    PubMed

    Shah, Neel B; Tande, Aaron J; Patel, Robin; Berbari, Elie F

    2015-12-01

    In an effort to improve mobility and alleviate pain from degenerative and connective tissue joint disease, an increasing number of individuals are undergoing prosthetic joint replacement in the United States. Joint replacement is a highly effective intervention, resulting in improved quality of life and increased independence [1]. By 2030, it is predicted that approximately 4 million total hip and knee arthroplasties will be performed yearly in the United States [2]. One of the major complications associated with this procedure is prosthetic joint infection (PJI), occurring at a rate of 1-2% [3-7]. In 2011, the Musculoskeletal Infectious Society created a unifying definition for prosthetic joint infection [8]. The following year, the Infectious Disease Society of America published practice guidelines that focused on the diagnosis and management of PJI. These guidelines focused on the management of commonly encountered organisms associated with PJI, including staphylococci, streptococci and select aerobic Gram-negative bacteria. However, with the exception of Propionibacterium acnes, management of other anaerobic organisms was not addressed in these guidelines [1]. Although making up approximately 3-6% of PJI [9,10], anaerobic microorganisms cause devastating complications, and similar to the more common organisms associated with PJI, these bacteria also result in significant morbidity, poor outcomes and increased health-care costs. Data on diagnosis and management of anaerobic PJI is mostly derived from case reports, along with a few cohort studies [3]. There is a paucity of published data outlining factors associated with risks, diagnosis and management of anaerobic PJI. We therefore reviewed available literature on anaerobic PJI by systematically searching the PubMed database, and collected data from secondary searches to determine information on pathogenesis, demographic data, clinical features, diagnosis and management. We focused our search on five commonly

  13. Steroid injections - tendon, bursa, joint

    MedlinePlus

    ... a small amount of corticosteroid and a local anesthetic into the bursa. JOINT Any joint problem, such ... A small amount of corticosteroid and a local anesthetic will be injected into the joint. TENDON A ...

  14. High pressure ceramic joint

    DOEpatents

    Ward, M.E.; Harkins, B.D.

    1993-11-30

    Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present joint when used with recuperators increases the use of ceramic components which do not react to highly corrosive gases. Thus, the present joint used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present joint is comprised of a first ceramic member, a second ceramic member, a mechanical locking device having a groove defined in one of the first ceramic member and the second ceramic member. The joint and the mechanical locking device is further comprised of a refractory material disposed in the groove and contacting the first ceramic member and the second ceramic member. The present joint mechanically provides a high strength load bearing joint having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures. 4 figures.

  15. [Classification and Treatment of Sacroiliac Joint Dislocation].

    PubMed

    Tan, Zhen; Huang, Zhong; Li, Liang; Meng, Wei-Kun; Liu, Lei; Zhang, Hui; Wang, Guang-Lin; Huang, Fu-Guo

    2017-09-01

    To develop a renewed classification and treatment regimen for sacroiliac joint dislocation. According to the direction of dislocation of sacroiliac joint,combined iliac,sacral fractures,and fracture morphology,sacroiliac joint dislocation was classified into 4 types. Type Ⅰ (sacroiliac anterior dislocation): main fracture fragments of posterior iliac wing dislocated in front of sacroiliac joint. Type Ⅱ (sacroiliac posterior dislocation): main fracture fragments of posterior iliac wing dislocated in posterior of sacroiliac joint. Type Ⅲ (Crescent fracturedislocation of the sacroiliac joint): upward dislocation of posterior iliac wing with oblique fracture through posterior iliac wing. Type ⅢA: a large crescent fragment and dislocation comprises no more than onethird of sacroiliac joint,which is typically inferior. Type ⅢB: intermediatesize crescent fragment and dislocation comprises between one and twothirds of joint. Type ⅢC: a small crescent fragment where dislocation comprises most,but not the entire joint. Different treatment regimens were selected for different types of fractures. Treatment for type Ⅰ sacroiliac joint dislocation: anterior iliac fossa approach pry stripping reset; sacroiliac joint fixed with sacroiliac screw through percutaneous. Treatment for type Ⅱ sacroiliac joint dislocation: posterior sacroiliac joint posterior approach; sacroiliac joint fixed with sacroiliac screw under computer guidance. Treatment for type ⅢA and ⅢB sacroiliac joint dislocation: posterior sacroiliac joint approach; sacroiliac joint fixed with reconstruction plate. Treatment for type ⅢC sacroiliac joint dislocation: sacroiliac joint closed reduction; sacroiliac joint fixed with sacroiliac screw through percutaneous. Treatment for type Ⅳ sacroiliac joint dislocation: posterior approach; sacroiliac joint fixed with spinal pelvic fixation. Results of 24 to 72 months patient follow-up (mean 34.5 months): 100% survival,100% wound healing,and 100

  16. Metal to ceramic sealed joint

    DOEpatents

    Lasecki, J.V.; Novak, R.F.; McBride, J.R.

    1991-08-27

    A metal to ceramic sealed joint which can withstand wide variations in temperature and maintain a good seal is provided for use in a device adapted to withstand thermal cycling from about 20 to about 1000 degrees C. The sealed joint includes a metal member, a ceramic member having an end portion, and an active metal braze forming a joint to seal the metal member to the ceramic member. The joint is positioned remote from the end portion of the ceramic member to avoid stresses at the ends or edges of the ceramic member. The sealed joint is particularly suited for use to form sealed metal to ceramic joints in a thermoelectric generator such as a sodium heat engine where a solid ceramic electrolyte is joined to metal parts in the system. 11 figures.

  17. Metal to ceramic sealed joint

    DOEpatents

    Lasecki, John V.; Novak, Robert F.; McBride, James R.

    1991-01-01

    A metal to ceramic sealed joint which can withstand wide variations in temperature and maintain a good seal is provided for use in a device adapted to withstand thermal cycling from about 20 to about 1000 degrees C. The sealed joint includes a metal member, a ceramic member having an end portion, and an active metal braze forming a joint to seal the metal member to the ceramic member. The joint is positioned remote from the end portion of the ceramic member to avoid stresses at the ends or edges of the ceramic member. The sealed joint is particularly suited for use to form sealed metal to ceramic joints in a thermoelectric generator such as a sodium heat engine where a solid ceramic electrolyte is joined to metal parts in the system.

  18. [A primary application and evaluation of temporomandibular joint replacement with stock prosthesis].

    PubMed

    Zhang, Xiao-hu; Chen, Min-jie; Qiu, Ya-ting; Yang, Chi

    2012-06-01

    To evaluate the effect of total joint replacement in treatment of temporomandibular joint(TMJ) osteoarthropathy with stock prostheses. Six female patients involving 10 joints (2 unilateral and 4 bilateral), with an average age of 59 years old, were involved in this study. Three patients (5 joints) were diagnosed as internal derangement in V stage depending on MRI, 3D-CT findings and clinical characteristics. The other 3 patients (5 joints) had histories of failed temporomandibular joint operation using costochondral graft or temporalis fascial flap. The maximal mouth opening was 1.9 cm on average (range, 1.0 to 2.9cm). All the joints were replaced with Biomet standard prosthesis under general anesthesia. The follow-up period was from 7 to 49 months (average, 17.5 months). All the operations were successfully performed. Heterotopic ossification happened in a bilateral case 1 year postoperatively. One patient with bilateral joint disease complained of severe uncomfortable feeling in the region of the ears and the temples, although there was no significant positive signs according to an ENT examination. Pain relief of the joint and mouth opening improvement were significant in 4 patients. No failure was noted secondary to infection or loosening of the prostheses. The occlusal relationship kept stable postoperatively in all cases. Total TMJ joint replacement with standard prosthesis is a good choice for TMJ reconstruction. It can significantly reduce joint pain and the mouth opening limitation resulted from osteoarthritis. Long-term result remains to be evaluated based on a long-term follow-up.

  19. Inpatient mortality after elective primary total hip and knee joint arthroplasty in Botswana.

    PubMed

    Lisenda, Laughter; Mokete, Lipalo; Mkubwa, Joseph; Lukhele, Mkhululi

    2016-12-01

    Total hip and knee joint arthroplasty (TJA) rank among the most successful orthopaedic operations. Several developing countries in Africa have started to perform these procedures that are routine in developed countries. The aims of this study were to measure the incidence and assess the determinants of in-hospital mortality after elective primary TJA in our unit and compare it with published data. This was a retrospective study of the first consecutive cohort of patients who underwent elective primary TJA in Princess Marina Hospital, Botswana between March 2009 and October 2015 (6.5 years). 346 elective joint replacements were performed comprising 153 total hip arthroplasties (THA) and 193 total knee arthroplasties (TKA); 36 % of the THA were in female patients and 82 % of TKA were in females. The mean age was 64.5 years (range 26-86). Three patients died giving an inpatient mortality rate of 0.86 %. These three mortalities represent 1.55 % (three out of 193) of all the TKA. There were no deaths after THA. The cause of mortality in two patients was an adverse cardiac event while the third mortality was due to pulmonary embolism. The inpatient mortality rate of 0.86 % following TJA is higher than the reported rates in the developed countries but comparable with data from other developing countries. The inpatient mortality rate following TKA was higher than that following THA and cardiovascular events proved to be the main cause of death. We recommend formal cardiology assessment and close peri-operative monitoring of all patients with a history of cardiovascular disease undergoing TJA.

  20. Social Media and Total Joint Arthroplasty: An Analysis of Patient Utilization on Instagram.

    PubMed

    Ramkumar, Prem N; Navarro, Sergio M; Haeberle, Heather S; Chughtai, Morad; Flynn, Megan E; Mont, Michael A

    2017-09-01

    The purpose of this study was to analyze the nature of shared content of total joint arthroplasty patients on Instagram. Specifically, we evaluated social media posts for: (1) perspective and timing; (2) tone; (3) focus (activities of daily living [ADLs], rehabilitation, return-to-work); and (4) the comparison between hip and knee arthroplasties. A search of the public Instagram domain was performed over a 6-month period. Total hip and knee arthroplasties (THA and TKA) were selected for the analysis using the following terms: "#totalhipreplacement," "#totalkneereplacement," and associated terms. 1287 individual public posts of human subjects were shared during the period. A categorical scoring system was utilized for media format (photo or video), time (preoperative, perioperative, or postoperative) period, tone (positive or negative), return-to-work, ADLs, rehabilitation, surgical site, radiograph image, satisfaction, and dissatisfaction. Ninety-one percent of the posts were shared during the postoperative period. Ninety-three percent of posts had a positive tone. Thirty-four percent of posts focused on both ADLs and 33.8% on rehabilitation. TKA patients shared more about their surgical site (14.5% vs 3.3%, P < .001) and rehabilitation (58.9% vs 8.8%, P < .001) than THA patients, whereas THA patients shared more about ADLs than TKA patients (60.5% vs 7.6%, P < .001). When sharing their experience on Instagram, arthroplasty patients did so with a positive tone, starting a week after surgery. TKA posts focused more on rehabilitation and wound healing than THA patients, whereas THA patients shared more posts on ADLs. The analysis of social media posts provides insight into what matters to patients after total joint arthroplasty. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Sacroiliac joint tuberculosis

    PubMed Central

    Govender, S.

    2006-01-01

    Infections of the sacroiliac joint are uncommon and the diagnosis is usually delayed. In a retrospective study, 17 patients who had been treated for tuberculosis sacroiliitis between 1994 and 2004 were reviewed. Two patients were excluded due to a short follow-up (less than 2 years). Low back pain and difficulty in walking were the most common presenting features. Two patients presented with a buttock abscess and spondylitis of the lumbar spine was noted in two patients. The Gaenslen’s and FABER (flexion, abduction and external rotation) tests were positive in all patients. Radiological changes included loss of cortical margins with erosion of the joints. An open biopsy and curettage was performed in all patients; histology revealed chronic infection and acid-fast bacilli were isolated in nine patients. Antituberculous (TB) medication was administered for 18 months and the follow-up ranged from 3 to 10 years (mean: 5 years). The sacroiliac joint fused spontaneously within 2 years. Although all patients had mild discomfort in the lower back following treatment they had no difficulty in walking. Sacroiliac joint infection must be included in the differential diagnosis of lower back pain and meticulous history and clinical evaluation of the joint are essential. PMID:16673102

  2. Augmented Reality-Guided Lumbar Facet Joint Injections.

    PubMed

    Agten, Christoph A; Dennler, Cyrill; Rosskopf, Andrea B; Jaberg, Laurenz; Pfirrmann, Christian W A; Farshad, Mazda

    2018-05-08

    The aim of this study was to assess feasibility and accuracy of augmented reality-guided lumbar facet joint injections. A spine phantom completely embedded in hardened opaque agar with 3 ring markers was built. A 3-dimensional model of the phantom was uploaded to an augmented reality headset (Microsoft HoloLens). Two radiologists independently performed 20 augmented reality-guided and 20 computed tomography (CT)-guided facet joint injections each: for each augmented reality-guided injection, the hologram was manually aligned with the phantom container using the ring markers. The radiologists targeted the virtual facet joint and tried to place the needle tip in the holographic joint space. Computed tomography was performed after each needle placement to document final needle tip position. Time needed from grabbing the needle to final needle placement was measured for each simulated injection. An independent radiologist rated images of all needle placements in a randomized order blinded to modality (augmented reality vs CT) and performer as perfect, acceptable, incorrect, or unsafe. Accuracy and time to place needles were compared between augmented reality-guided and CT-guided facet joint injections. In total, 39/40 (97.5%) of augmented reality-guided needle placements were either perfect or acceptable compared with 40/40 (100%) CT-guided needle placements (P = 0.5). One augmented reality-guided injection missed the facet joint space by 2 mm. No unsafe needle placements occurred. Time to final needle placement was substantially faster with augmented reality guidance (mean 14 ± 6 seconds vs 39 ± 15 seconds, P < 0.001 for both readers). Augmented reality-guided facet joint injections are feasible and accurate without potentially harmful needle placement in an experimental setting.

  3. [Temporo-mandibular joint. Morpho-functional considerations].

    PubMed

    Scutariu, M D; Indrei, Anca

    2004-01-01

    The temporo-mandibular joint is distinguished from most other synovial joints of the body by two features: 1. the two jointed components carry teeth whose position and occlusion introduce a very strong influence on the movements of the temporo-mandibular joint and 2. its articular surfaces are not covered by hyaline cartilage, but by a dense, fibrous tissue. This paper describes the parts of the temporo-mandibular joint: the articular surfaces (the condylar process of the mandible and the glenoid part of the temporal bone), the fibrocartilaginous disc which is interposed between the mandibular and the temporal surface, the fibrous capsule of the temporo-mandibular joint and the ligaments of this joint. All these parts present a very strong adaptation at the important functions of the temporo-mandibular joint.

  4. Utilization of Facet Joint and Sacroiliac Joint Interventions in Medicare Population from 2000 to 2014: Explosive Growth Continues!

    PubMed

    Manchikanti, Laxmaiah; Hirsch, Joshua A; Pampati, Vidyasagar; Boswell, Mark V

    2016-10-01

    Increasing utilization of interventional techniques in managing chronic spinal pain, specifically facet joint interventions and sacroiliac joint injections, is a major concern of healthcare policy makers. We analyzed the patterns of utilization of facet and sacroiliac joint interventions in managing chronic spinal pain. The results showed significant increase of facet joint interventions and sacroiliac joint injections from 2000 to 2014 in Medicare FFS service beneficiaries. Overall, the Medicare population increased 35 %, whereas facet joint and sacroiliac joint interventions increased 313.3 % per 100,000 Medicare population with an annual increase of 10.7 %. While the increases were uniform from 2000 to 2014, there were some decreases noted for facet joint interventions in 2007, 2010, and 2013, whereas for sacroiliac joint injections, the decreases were noted in 2007 and 2013. The increases were for cervical and thoracic facet neurolysis at 911.5 % compared to lumbosacral facet neurolysis of 567.8 %, 362.9 % of cervical and thoracic facet joint blocks, 316.9 % of sacroiliac joints injections, and finally 227.3 % of lumbosacral facet joint blocks.

  5. Ball-joint grounding ring

    NASA Technical Reports Server (NTRS)

    Aperlo, P. J. A.; Buck, P. A.; Weldon, V. A.

    1981-01-01

    In ball and socket joint where electrical insulator such as polytetrafluoroethylene is used as line to minimize friction, good electrical contact across joint may be needed for lightning protection or to prevent static-charge build-up. Electrical contact is maintained by ring of spring-loaded fingers mounted in socket. It may be useful in industry for cranes, trailers, and other applications requiring ball and socket joint.

  6. [Joint contractures in nursing textbooks].

    PubMed

    Bartoszek, G; Meyer, G; Thiesemann, R

    2014-01-01

    The transparency criteria of the German statutory health insurance on joint contracture prevention have led to controversies about the appropriate assessment, prevention and treatment as well as to various actions in nursing practice. However, appropriate nursing assessments and proven treatment options are lacking so far. It is unclear whether textbooks on nursing reflect these uncertainties. Search for textbooks on nursing through internet-based search engines and publisher registers, data extraction by one investigator and control by a second. A total of 35 textbooks with contributions on joint contractures were identified of which 25 included a definition, causes/risk factors are presented in 32 textbooks and assessments are presented in 5 books. Most often positioning into a physiological or functional neutral position and passive moving of limbs are recommended as passive prophylaxis. Recommended therapeutic and preventive options do not differ. None of the textbooks reflect that there is a lack of scientific knowledge on the subject. Textbooks on nursing do not deal with complete and scientific sound information on joint contractures.

  7. Estimation of Finger Joint Angles Based on Electromechanical Sensing of Wrist Shape.

    PubMed

    Kawaguchi, Junki; Yoshimoto, Shunsuke; Kuroda, Yoshihiro; Oshiro, Osamu

    2017-09-01

    An approach to finger motion capture that places fewer restrictions on the usage environment and actions of the user is an important research topic in biomechanics and human-computer interaction. We proposed a system that electrically detects finger motion from the associated deformation of the wrist and estimates the finger joint angles using multiple regression models. A wrist-mounted sensing device with 16 electrodes detects deformation of the wrist from changes in electrical contact resistance at the skin. In this study, we experimentally investigated the accuracy of finger joint angle estimation, the adequacy of two multiple regression models, and the resolution of the estimation of total finger joint angles. In experiments, both the finger joint angles and the system output voltage were recorded as subjects performed flexion/extension of the fingers. These data were used for calibration using the least-squares method. The system was found to be capable of estimating the total finger joint angle with a root-mean-square error of 29-34 degrees. A multiple regression model with a second-order polynomial basis function was shown to be suitable for the estimation of all total finger joint angles, but not those of the thumb.

  8. 14 CFR 23.693 - Joints.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Systems § 23.693 Joints. Control system joints (in push-pull systems) that are subject to angular motion... factor may be reduced to 2.0 for joints in cable control systems. For ball or roller bearings, the...

  9. Wrist joint assembly

    NASA Technical Reports Server (NTRS)

    Kersten, L.; Johnson, J. D. (Inventor)

    1978-01-01

    A wrist joint assembly is provided for use with a mechanical manipulator arm for finely positioning an end-effector carried by the wrist joint on the terminal end of the manipulator arm. The wrist joint assembly is pivotable about a first axis to produce a yaw motion, a second axis is to produce a pitch motion, and a third axis to produce a roll motion. The wrist joint assembly includes a disk segment affixed to the terminal end of the manipulator arm and a first housing member, a second housing member, and a third housing member. The third housing member and the mechanical end-effector are moved in the yaw, pitch, and roll motion. Drive means are provided for rotating each of the housings about their respective axis which includes a cluster of miniature motors having spur gears carried on the output drive shaft which mesh with a center drive gear affixed on the housing to be rotated.

  10. Multispectral diffuse optical tomography of finger joints

    NASA Astrophysics Data System (ADS)

    Lighter, Daniel; Filer, Andrew; Dehghani, Hamid

    2017-07-01

    Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by synovial inflammation. The current treatment paradigm for earlier, more aggressive therapy places importance on development of functional imaging modalities, capable of quantifying joint changes at the earliest stages. Diffuse optical tomography (DOT) has shown great promise in this regard, due to its cheap, non-invasive, non-ionizing and high contrast nature. Underlying pathological activity in afflicted joints leads to altered optical properties of the synovial region, with absorption and scattering increasing. Previous studies have used these optical changes as features for classifying diseased joints from healthy. Non-tomographic, single wavelength, continuous wave (CW) measurements of trans-illuminated joints have previously reported achieving this with specificity and sensitivity in the range 80 - 90% [1]. A single wavelength, frequency domain DOT system, combined with machine learning techniques, has been shown to achieve sensitivity and specificity in the range of 93.8 - 100% [2]. A CW system is presented here which collects data at 5 wavelengths, enabling reconstruction of pathophysiological parameters such as oxygenation and total hemoglobin, with the aim of identifying localized hypoxia and angiogenesis associated with inflammation in RA joints. These initial studies focus on establishing levels of variation in recovered parameters from images of healthy controls.

  11. The influence of patellofemoral joint contact geometry on the modeling of three dimensional patellofemoral joint forces.

    PubMed

    Powers, Christopher M; Chen, Yu-Jen; Scher, Irving; Lee, Thay Q

    2006-01-01

    The purpose of this study was to determine the influence of patellofemoral joint contact geometry on the modeling of three-dimensional patellofemoral joint forces. To achieve this goal, patellofemoral joint reaction forces (PFJRFs) that were measured from an in-vitro cadaveric set-up were compared to PFJRFs estimated from a computer model that did not consider patellofemoral joint contact geometry. Ten cadaver knees were used in this study. Each was mounted on a custom jig that was fixed to an Instron frame. Quadriceps muscle loads were accomplished using a pulley system and weights. The force in the patellar ligament was obtained using a buckle transducer. To quantify the magnitude and direction of the PFJRF, a six-axis load cell was incorporated into the femoral fixation system so that a rigid body assumption could be made. PFJRF data were obtained at 0 degrees , 20 degrees , 40 degrees and 60 degrees of knee flexion. Following in vitro testing, SIMM modeling software was used to develop computational models based on the three-dimensional coordinates (Microscribe digitizer) of individual muscle and patellar ligament force vectors obtained from the cadaver knees. The overall magnitude of the PFJRF estimated from the computer generated models closely matched the direct measurements from the in vitro set-up (Pearson's correlation coefficient, R(2)=0.91, p<0.001). Although the computational model accurately estimated the posteriorly directed forces acting on the joint, some discrepancies were noted in the forces acting in the superior and lateral directions. These differences however, were relatively small when expressed as a total of the overall PFJRF magnitude.

  12. Vascularised knee joint transplantation in man: the first two years experience.

    PubMed

    Kirschner, M H; Brauns, L; Gonschorek, O; Bühren, V; Hofmann, G O

    2000-04-01

    To describe our early experience with a new technique for restoring destroyed knee joints to give reasonable functional results. Observational clinical trial. Level-1-Trauma centre, Germany. 5 patients with large bone defects of the knee and loss of the extensor apparatus caused either by serious injury alone, or infection after serious injury. Transplantation of fresh and perfused knee joints with a vascular pedicle from multiorgan donors under immunosuppression. Ability to walk, need to remove one transplanted joint. Four patients are able to walk, the range of movement being from 50 degrees-120 degrees. The first patient additionally had to be provided with a total knee joint arthroplasty. In the third patient the graft became infected and had to be removed. She finally had an arthrodesis and bone lengthening by the Ilizarov technique. Transplantation of the knee joint may be an alternative to bone lengthening or amputation for patients with total loss of the extensor apparatus.

  13. Product evaluation : Ruscoe 983 joint sealant

    DOT National Transportation Integrated Search

    1986-07-10

    This report contains a product evaluation of Ruscoe's 983 joint sealant. Ruscoe 983 is an asphalt base single compound joint sealant. It contains an aluminum fortified adhesive and is designed for use on highway expansion joints, bridge joints, and r...

  14. Are the Kinematics of the Knee Joint Altered during the Loading Response Phase of Gait in Individuals with Concurrent Knee Osteoarthritis and Complaints of Joint Instability? A Dynamic Stereo X-ray Study

    PubMed Central

    Farrokhi, Shawn; Tashman, Scott; Gil, Alexandra B.; Klatt, Brian A.; Fitzgerald, G. Kelley

    2011-01-01

    Background Joint instability has been suggested as a risk factor for knee osteoarthritis and a cause of significant functional declines in those with symptomatic disease. However, the relationship between altered knee joint mechanics and self-reports of instability in individuals with knee osteoarthritis remains unclear. Methods Fourteen subjects with knee osteoarthritis and complaints of joint instability and 12 control volunteers with no history of knee disease were recruited for this study. Dynamic stereo X-ray technology was used to assess the three-dimensional kinematics of the knee joint during the loading response phase of gait. Findings Individuals with concurrent knee osteoarthritis and joint instability demonstrated significantly reduced flexion and internal/external rotation knee motion excursions during the loading response phase of gait (P < 0.01), while the total abduction/adduction range of motion was increased (P < 0.05). In addition, the coronal and transverse plane alignment of the knee joint at initial contact was significantly different (P < 0.05) for individuals with concurrent knee osteoarthritis and joint instability. However, the anteroposterior and mediolateral tibiofemoral joint positions at initial contact and the corresponding total joint translations were similar between groups during the loading phase of gait. Interpretations The rotational patterns of tibiofemoral joint motion and joint alignments reported for individuals with concurrent knee osteoarthritis and joint instability are consistent with those previously established for individuals with knee osteoarthritis. Furthermore, the findings of similar translatory tibiofemoral motion between groups suggest that self-reports of episodic joint instability in individuals with knee osteoarthritis may not necessarily be associated with adaptive alterations in joint arthrokinematics. PMID:22071429

  15. Gene-expression changes in knee-joint tissues with aging and menopause: implications for the joint as an organ

    PubMed Central

    Rollick, Natalie C; Lemmex, Devin B; Ono, Yohei; Reno, Carol R; Hart, David A; Lo, Ian KY; Thornton, Gail M

    2018-01-01

    Background When considering the “joint as an organ”, the tissues in a joint act as complementary components of an organ, and the “set point” is the cellular activity for homeostasis of the joint tissues. Even in the absence of injury, joint tissues have adaptive responses to processes, like aging and menopause, which result in changes to the set point. Purpose The purpose of this study in a preclinical model was to investigate age-related and menopause-related changes in knee-joint tissues with the hypothesis that tissues will change in unique ways that reflect their differing contributions to maintaining joint function (as measured by joint laxity) and the differing processes of aging and menopause. Methods Rabbit knee-joint tissues from three groups were evaluated: young adult (gene expression, n=8; joint laxity, n=7; water content, n=8), aging adult (gene expression, n=6; joint laxity, n=7; water content, n=5), and menopausal adult (gene expression, n=8; joint laxity, n=7; water content, n=8). Surgical menopause was induced with ovariohysterectomy surgery and gene expression was assessed using reverse-transcription quantitative polymerase chain reaction. Results Aging resulted in changes to 37 of the 150 gene–tissue combinations evaluated, and menopause resulted in changes to 39 of the 150. Despite the similar number of changes, only eleven changes were the same in both aging and menopause. No differences in joint laxity were detected comparing young adult rabbits with aging adult rabbits or with menopausal adult rabbits. Conclusion Aging and menopause affected the gene-expression patterns of the tissues of the knee joint differently, suggesting unique changes to the set point of the knee. Interestingly, aging and menopause did not affect knee-joint laxity, suggesting that joint function was maintained, despite changes in gene expression. Taken together, these findings support the theory of the joint as an organ where the tissues of the joint adapt to

  16. Incidence of Infection and Inhospital Mortality in Patients With Chronic Renal Failure After Total Joint Arthroplasty.

    PubMed

    Erkocak, Omer F; Yoo, Joanne Y; Restrepo, Camilo; Maltenfort, Mitchell G; Parvizi, Javad

    2016-11-01

    Patients with chronic renal failure (CRF) may require total joint arthroplasty (TJA) to treat degenerative joint disease, fractures, osteonecrosis, or amyloid arthropathy. There have been conflicting results, however, regarding outcomes of TJA in patients with chronic renal disease. The aim of this case-controlled study was to determine the outcome of TJA in patients with CRF, with particular interest in the incidence of infections and inhospital mortality. We queried our electronic database to determine which patients among the 29,389 TJAs performed at our institution between January 2000 and June 2012 had a diagnosis of CRF. A total of 359 CRF patients were identified and matched for procedure, gender, age (±4 years), date of surgery (±2 years), and body mass index (±5 kg/m 2 ) in a 2:1 ratio to 718 control patients. The incidence of infection and inhospital mortality was not significantly different between the nondialysis CRF patients and controls, whereas it was significantly higher in dialysis-dependent end-stage renal failure patients compared to controls. Of the 50 CRF patients receiving hemodialysis, 10 (20%) developed surgical site infection, of which 4 (8%) were periprosthetic joint infection, and 4 (8%) died during hospital stay. The odds ratio for infection in the dialysis group was 7.54 (95% confidence interval: 2.83-20.12) and 10.46 (95% confidence interval: 1.67-65.34) for the inhospital mortality. We conclude that end-stage renal failure patients receiving hemodialysis have higher postoperative infection and inhospital mortality rates after an elective TJA procedure, whereas nondialysis CRF patients have similar outcomes compared with the general TJA population. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. A novel multi-item joint replenishment problem considering multiple type discounts.

    PubMed

    Cui, Ligang; Zhang, Yajun; Deng, Jie; Xu, Maozeng

    2018-01-01

    In business replenishment, discount offers of multi-item may either provide different discount schedules with a single discount type, or provide schedules with multiple discount types. The paper investigates the joint effects of multiple discount schemes on the decisions of multi-item joint replenishment. In this paper, a joint replenishment problem (JRP) model, considering three discount (all-unit discount, incremental discount, total volume discount) offers simultaneously, is constructed to determine the basic cycle time and joint replenishment frequencies of multi-item. To solve the proposed problem, a heuristic algorithm is proposed to find the optimal solutions and the corresponding total cost of the JRP model. Numerical experiment is performed to test the algorithm and the computational results of JRPs under different discount combinations show different significance in the replenishment cost reduction.

  18. Thoracic costotransverse joint pain patterns: a study in normal volunteers.

    PubMed

    Young, Brian A; Gill, Howard E; Wainner, Robert S; Flynn, Timothy W

    2008-10-15

    Pain referral patterns of asymptomatic costotransverse joints have not been established. The objective of this study was to determine the pain referral patterns of asymptomatic costotransverse joints via provocative intra-articular injection. Eight asymptomatic male volunteers received a combined total of 21 intra-articular costotransverse joint injections. Fluoroscopic imaging was used to identify and isolate each costotransverse joint and guide placement of a 25 gauge, 2.5 inch spinal needle into the costotransverse joint. Following contrast medium injection, the quality, intensity, and distribution of the resultant pain produced were recorded. Of the 21 costotransverse joint injections, 16 (76%) were classified as being intra-articular via arthrograms taken at the time of injection, and 14 of these injections produced a pain sensation distinctly different from that of needle placement. Average pain produced was 3.3/10 on a 0-10 verbal pain scale. Pain was described generally as a deep, dull ache, and pressure sensation. Pain patterns were located superficial to the injected joint, with only the right T2 injections showing referred pain 2 segments cranially and caudally. No chest wall, upper extremity or pseudovisceral pains were reported. This study provides preliminary data of the pain referral patterns of costotransverse joints. Further research is needed to compare these findings with those elicited from symptomatic subjects.

  19. Patient-specific musculoskeletal modeling of the hip joint for preoperative planning of total hip arthroplasty: A validation study based on in vivo measurements

    PubMed Central

    Schick, Fabian; Asseln, Malte; Damm, Philipp; Radermacher, Klaus

    2018-01-01

    Validation of musculoskeletal models for application in preoperative planning is still a challenging task. Ideally, the simulation results of a patient-specific musculoskeletal model are compared to corresponding in vivo measurements. Currently, the only possibility to measure in vivo joint forces is to implant an instrumented prosthesis in patients undergoing a total joint replacement. In this study, a musculoskeletal model of the AnyBody Modeling System was adapted patient-specifically and validated against the in vivo hip joint force measurements of ten subjects performing one-leg stance and level walking. The impact of four model parameters was evaluated; hip joint width, muscle strength, muscle recruitment, and type of muscle model. The smallest difference between simulated and in vivo hip joint force was achieved by using the hip joint width measured in computed tomography images, a muscle strength of 90 N/cm2, a third order polynomial muscle recruitment, and a simple muscle model. This parameter combination reached mean deviations between simulation and in vivo measurement during the peak force phase of 12% ± 14% in magnitude and 11° ± 5° in orientation for one-leg stance and 8% ± 6% in magnitude and 10° ± 5° in orientation for level walking. PMID:29649235

  20. What makes patients aware of their artificial knee joint?

    PubMed

    Loth, F L; Liebensteiner, M C; Giesinger, J M; Giesinger, K; Bliem, H R; Holzner, B

    2018-01-08

    Joint awareness was recently introduced as a new concept for outcome assessment after total knee arthroplasty (TKA). Findings from qualitative and psychometric studies suggest that joint awareness is a distinct concept especially relevant to patients with good surgical outcome and patients at late follow-up time points. The aim of this study was to improve the understanding of the concept of joint awareness by identifying situations in which patients are aware of their artificial knee joint and to investigate what bodily sensations and psychological factors raise a patient's awareness of her/his knee. In addition, we evaluated the relative importance of patient-reported outcome parameters that are commonly assessed in orthopaedics. Qualitative interviews were conducted with patients being at least 12 months after TKA. The interviews focused on when, where and for what reasons patients were aware of their artificial knee joint. To evaluate the relative importance of 'joint awareness' after TKA among nine commonly assessed outcome parameters (e.g. pain or stiffness), we collected importance ratings ('0' indicating no importance at all and '10' indicating high importance). We conducted interviews with 40 TKA patients (mean age 69.0 years; 65.0% female). Joint awareness was found to be frequently triggered by kneeling on the floor (30%), climbing stairs (25%), and starting up after resting (25%). Patients reported joint awareness to be related to activities of daily living (68%), specific movements (60%), or meteoropathy (18%). Sensations causing joint awareness included pain (45%) or stiffness (15%). Psychological factors raising a patient's awareness of his/her knee comprised for example feelings of insecurity (15%), and fears related to revision surgeries, inflammations or recurring pain (8%). Patients' importance ratings of outcome parameters were generally high and did not allow differentiating clearly among them. We have identified a wide range of situations

  1. Simulation of in vivo dynamics during robot assisted joint movement.

    PubMed

    Bobrowitsch, Evgenij; Lorenz, Andrea; Wülker, Nikolaus; Walter, Christian

    2014-12-16

    Robots are very useful tools in orthopedic research. They can provide force/torque controlled specimen motion with high repeatability and precision. A method to analyze dissipative energy outcome in an entire joint was developed in our group. In a previous study, a sheep knee was flexed while axial load remained constant during the measurement of dissipated energy. We intend to apply this method for the investigation of osteoarthritis. Additionally, the method should be improved by simulation of in vivo knee dynamics. Thus, a new biomechanical testing tool will be developed for analyzing in vitro joint properties after different treatments. Discretization of passive knee flexion was used to construct a complex flexion movement by a robot and simulate altering axial load similar to in vivo sheep knee dynamics described in a previous experimental study. The robot applied an in vivo like axial force profile with high reproducibility during the corresponding knee flexion (total standard deviation of 0.025 body weight (BW)). A total residual error between the in vivo and simulated axial force was 0.16 BW. Posterior-anterior and medio-lateral forces were detected by the robot as a backlash of joint structures. Their curve forms were similar to curve forms of corresponding in vivo measured forces, but in contrast to the axial force, they showed higher total standard deviation of 0.118 and 0.203 BW and higher total residual error of 0.79 and 0.21 BW for posterior-anterior and medio-lateral forces respectively. We developed and evaluated an algorithm for the robotic simulation of complex in vivo joint dynamics using a joint specimen. This should be a new biomechanical testing tool for analyzing joint properties after different treatments.

  2. Adjustable bias column end joint assembly

    NASA Technical Reports Server (NTRS)

    Wallsom, Richard E. (Inventor); Bush, Harold G. (Inventor)

    1994-01-01

    An adjustable mechanical end joint system for connecting structural column elements and eliminating the possibility of free movement between joint halves during loading or vibration has a node joint body having a cylindrical engaging end and a column end body having a cylindrical engaging end. The column end joint body has a compressible preload mechanism and plunger means housed therein. The compressible preload mechanism may be adjusted from the exterior of the column end joint body through a port.

  3. Are the kinematics of the knee joint altered during the loading response phase of gait in individuals with concurrent knee osteoarthritis and complaints of joint instability? A dynamic stereo X-ray study.

    PubMed

    Farrokhi, Shawn; Tashman, Scott; Gil, Alexandra B; Klatt, Brian A; Fitzgerald, G Kelley

    2012-05-01

    Joint instability has been suggested as a risk factor for knee osteoarthritis and a cause of significant functional decline in those with symptomatic disease. However, the relationship between altered knee joint mechanics and self-reports of instability in individuals with knee osteoarthritis remains unclear. Fourteen subjects with knee osteoarthritis and complaints of joint instability and 12 control volunteers with no history of knee disease were recruited for this study. Dynamic stereo X-ray technology was used to assess the three-dimensional kinematics of the knee joint during the loading response phase of gait. Individuals with concurrent knee osteoarthritis and joint instability demonstrated significantly reduced flexion and internal/external rotation knee motion excursions during the loading response phase of gait (P<0.01), while the total abduction/adduction range of motion was increased (P<0.05). In addition, the coronal and transverse plane alignment of the knee joint at initial contact was significantly different (P<0.05) for individuals with concurrent knee osteoarthritis and joint instability. However, the anteroposterior and mediolateral tibiofemoral joint positions at initial contact and the corresponding total joint translations were similar between groups during the loading phase of gait. The rotational patterns of tibiofemoral joint motion and joint alignments reported for individuals with concurrent knee osteoarthritis and joint instability are consistent with those previously established for individuals with knee osteoarthritis. Furthermore, the findings of similar translatory tibiofemoral motion between groups suggest that self-reports of episodic joint instability in individuals with knee osteoarthritis may not necessarily be associated with adaptive alterations in joint arthrokinematics. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. 14 CFR 23.693 - Joints.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.693 Joints. Control system joints (in push-pull systems) that are subject to angular motion... factor may be reduced to 2.0 for joints in cable control systems. For ball or roller bearings, the...

  5. 14 CFR 23.693 - Joints.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.693 Joints. Control system joints (in push-pull systems) that are subject to angular motion... factor may be reduced to 2.0 for joints in cable control systems. For ball or roller bearings, the...

  6. 14 CFR 23.693 - Joints.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.693 Joints. Control system joints (in push-pull systems) that are subject to angular motion... factor may be reduced to 2.0 for joints in cable control systems. For ball or roller bearings, the...

  7. 14 CFR 23.693 - Joints.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.693 Joints. Control system joints (in push-pull systems) that are subject to angular motion... factor may be reduced to 2.0 for joints in cable control systems. For ball or roller bearings, the...

  8. Quick-connect threaded attachment joint

    NASA Technical Reports Server (NTRS)

    Lucy, M. H.; Messick, W. R.; Vasquez, P.

    1979-01-01

    Joint is self-aligning and tightens with only sixty-five degrees of rotation for quick connects and disconnects. Made of injection-molded plastics or cast or machined aluminum, joint can carry wires, tubes, liquids, or gases. When two parts of joint are brought together, their shapes align them. Small projections on male section and slots on female section further aid alignment; slight rotation of male form engages projections in slots. At this point, threads engage and male section is rotated until joint is fully engaged.

  9. Assessment of the Patient-Centered and Family-Centered Care Experience of Total Joint Replacement Patients Using a Shadowing Technique.

    PubMed

    Marcus-Aiyeku, Ulanda; DeBari, Margaret; Salmond, Susan

    2015-01-01

    In 2030, when baby boomers reach 65 years of age and represent 18% of the population, it is anticipated that 67 million adults will have a diagnosis of arthritis increasing the demand for total hip and knee arthroplasty. With the growing emphasis on patient- and family-centered care, the aim of this project was to assess the patient experience of patients and families throughout the entire spectrum of the total joint replacement service line care at a university regional trauma hospital. A shadowing methodology as defined by the Institute for Health Improvement was utilized. Eight patient/family groups undergoing total joint replacements were shadowed. The mapped care experience included time, caregiver, activity, shadower observations, and impressions. Findings revealed inconsistencies in the delivery of patient- and family-centered care. Communication and interactions were predominantly provider-centric, with a focus on care routines versus the patient and family, and anticipation that care would be medically directed.

  10. Activity Levels in Healthy Older Adults: Implications for Joint Arthroplasty

    PubMed Central

    Thorp, Laura E.; Orozco, Diego; Block, Joel A.; Sumner, Dale R.; Wimmer, Markus A.

    2012-01-01

    This work evaluated activity levels in a group of healthy older adults to establish a target activity level for adults of similar age after total joint arthroplasty (TJA). With the decreasing age of TJA patients, it is essential to have a reference for activity level in younger patients as activity level affects quality of life and implant design. 54 asymptomatic, healthy older adults with no clinical evidence of lower extremity OA participated. The main outcome measure, average daily step count, was measured using an accelerometer-based activity monitor. On average the group took 8813 ± 3611 steps per day, approximately 4000 more steps per day than has been previously reported in patients following total joint arthroplasty. The present work provides a reference for activity after joint arthroplasty which is relevant given the projected number of people under the age of 65 who will undergo joint arthroplasty in the coming years. PMID:23577274

  11. The contribution of quasi-joint stiffness of the ankle joint to gait in patients with hemiparesis.

    PubMed

    Sekiguchi, Yusuke; Muraki, Takayuki; Kuramatsu, Yuko; Furusawa, Yoshihito; Izumi, Shin-Ichi

    2012-06-01

    The role of ankle joint stiffness during gait in patients with hemiparesis has not been clarified. The purpose of this study was to determine the contribution of quasi-joint stiffness of the ankle joint to spatiotemporal and kinetic parameters regarding gait in patients with hemiparesis due to brain tumor or stroke and healthy individuals. Spatiotemporal and kinetic parameters regarding gait in twelve patients with hemiparesis due to brain tumor or stroke and nine healthy individuals were measured with a 3-dimensional motion analysis system. Quasi-joint stiffness was calculated from the slope of the linear regression of the moment-angle curve of the ankle joint during the second rocker. There was no significant difference in quasi-joint stiffness among both sides of patients and the right side of controls. Quasi-joint stiffness on the paretic side of patients with hemiparesis positively correlated with maximal ankle power (r=0.73, P<0.01) and gait speed (r=0.66, P<0.05). In contrast, quasi-joint stiffness in controls negatively correlated with maximal ankle power (r=-0.73, P<0.05) and gait speed (r=-0.76, P<0.05). Our findings suggested that ankle power during gait might be generated by increasing quasi-joint stiffness in patients with hemiparesis. In contrast, healthy individuals might decrease quasi-joint stiffness to avoid deceleration of forward tilt of the tibia. Our findings might be useful for selecting treatment for increased ankle stiffness due to contracture and spasticity in patients with hemiparesis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Recent advances in computational mechanics of the human knee joint.

    PubMed

    Kazemi, M; Dabiri, Y; Li, L P

    2013-01-01

    Computational mechanics has been advanced in every area of orthopedic biomechanics. The objective of this paper is to provide a general review of the computational models used in the analysis of the mechanical function of the knee joint in different loading and pathological conditions. Major review articles published in related areas are summarized first. The constitutive models for soft tissues of the knee are briefly discussed to facilitate understanding the joint modeling. A detailed review of the tibiofemoral joint models is presented thereafter. The geometry reconstruction procedures as well as some critical issues in finite element modeling are also discussed. Computational modeling can be a reliable and effective method for the study of mechanical behavior of the knee joint, if the model is constructed correctly. Single-phase material models have been used to predict the instantaneous load response for the healthy knees and repaired joints, such as total and partial meniscectomies, ACL and PCL reconstructions, and joint replacements. Recently, poromechanical models accounting for fluid pressurization in soft tissues have been proposed to study the viscoelastic response of the healthy and impaired knee joints. While the constitutive modeling has been considerably advanced at the tissue level, many challenges still exist in applying a good material model to three-dimensional joint simulations. A complete model validation at the joint level seems impossible presently, because only simple data can be obtained experimentally. Therefore, model validation may be concentrated on the constitutive laws using multiple mechanical tests of the tissues. Extensive model verifications at the joint level are still crucial for the accuracy of the modeling.

  13. Double slotted socket spherical joint

    DOEpatents

    Bieg, Lothar F.; Benavides, Gilbert L.

    2001-05-22

    A new class of spherical joints is disclosed. These spherical joints are capable of extremely large angular displacements (full cone angles in excess of 270.degree.), while exhibiting no singularities or dead spots in their range of motion. These joints can improve or simplify a wide range of mechanical devices.

  14. Single stage treatment of ankylosis of the temporomandibular joint using patient-specific total joint replacement and virtual surgical planning.

    PubMed

    Haq, Jahrad; Patel, Nishma; Weimer, Katherine; Matthews, N Shaun

    2014-04-01

    Ankylosis of the temporomandibular joint (TMJ) is a debilitating condition that can result in pain, trismus, and a poor quality of life. It can be caused by injury, infection, and rheumatoid disease. Current management includes gap arthroplasty, interpositional arthroplasty, and reconstruction. Traditionally, joints are reconstructed using stock implants, or the procedure is done in two stages with an additional computed tomography (CT) scan between the resective and reconstructive procedures and use of stereolithographic models to aid the design of the definitive prostheses. We describe a technique for the resection of ankylosis and reconstruction of the joint in a single operation using virtually designed custom-made implants. Five patients with ankylosis of the TMJ had a single stage operation with reconstruction between 2010 and 2012. All had preoperative high-resolution CT with contrast angiography. During an international web-based teleconference between the surgeon and the engineer a virtual resection of the ankylosis was done using the reconstructed CT images. The bespoke cutting guides and implants were designed virtually at the same time and were then manufactured precisely using computer-aided design and manufacture (CAD-CAM) over 6 weeks. After release of the ankylosis and reconstruction, the patients underwent an exercise regimen to improve mouth opening. Follow-up was for a minimum of 6 months. Four patients had one operation, and one patient had two. Median/Mean maximum incisal opening increased from 0.6mm before operation to 25 mm afterwards (range 23-27), and there was minimal surgical morbidity. This new method effectively treats ankylosis of the TMJ in a single stage procedure. Fewer operations and hospital stays, and the maintenance of overall clinical outcome are obvious advantages. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  15. Hip joint replacement - slideshow

    MedlinePlus

    ... this page: //medlineplus.gov/ency/presentations/100006.htm Hip joint replacement - series—Normal anatomy To use the ... to slide 5 out of 5 Overview The hip joint is made up of two major parts: ...

  16. Sacroiliac joint pain - aftercare

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000610.htm Sacroiliac joint pain - aftercare To use the sharing features on this page, please enable JavaScript. The sacroiliac joint (SIJ) is a term used to describe ...

  17. Metacarpophalangeal joint arthroscopy: indications revisited.

    PubMed

    Choi, Alexander K Y; Chow, Esther C S; Ho, P C; Chow, Y Y

    2011-08-01

    Arthroscopic surgery has become the gold standard for the diagnosis and treatment of major joint disorders. With advancement in arthroscopic technique, arthroscopy has become feasible in most human joints, even those as small as the finger joints. The metacarpophalangeal joint (MCPJ) can become spacious with simple traction, the intra-articular anatomy is simple, and its major structures can be easily visualized and identified. However, MCPJ arthroscopy has never been popular. This article describes our experience with MCPJ arthroscopy and seeks to establish its role in clinical practice. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Can therapy dogs improve pain and satisfaction after total joint arthroplasty? A randomized controlled trial.

    PubMed

    Harper, Carl M; Dong, Yan; Thornhill, Thomas S; Wright, John; Ready, John; Brick, Gregory W; Dyer, George

    2015-01-01

    The use of animals to augment traditional medical therapies was reported as early as the 9th century but to our knowledge has not been studied in an orthopaedic patient population. The purpose of this study was to evaluate the role of animal-assisted therapy using therapy dogs in the postoperative recovery of patients after THA and TKA. We asked: (1) Do therapy dogs have an effect on patients' perception of pain after total joint arthroplasty as measured by the VAS? (3) Do therapy dogs have an effect on patients' satisfaction with their hospital stay after total joint arthroplasty as measured by the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS)? A randomized controlled trial of 72 patients undergoing primary unilateral THA or TKA was conducted. Patients were randomized to a 15-minute visitation with a therapy dog before physical therapy or standard postoperative physical therapy regimens. Both groups had similar demographic characteristics. Reduction in pain was assessed using the VAS after each physical therapy session, beginning on postoperative Day 1 and continuing for three consecutive sessions. To ascertain patient satisfaction, the proportion of patients selecting top-category ratings in each subsection of the HCAHPS was compared. Patients in the treatment group had lower VAS scores after each physical therapy session with a final VAS score difference of 2.4 units (animal-assisted therapy VAS, 1.7; SD, 0.97 [95% CI, 1.4-2.0] versus control VAS, 4.1; SD, 0.97 [95% CI, 3.8-4.4], p<0.001) after the third physical therapy session. Patients in the treatment group had a higher proportion of top-box HCAHPS scores in the following fields: nursing communication (33 of 36, 92% [95% CI, 78%-98%] versus 69%, 25 of 36 [95% CI, 52%-84%], p=0.035; risk ratio, 1.3 [95% CI of risk ratio, 1.0-1.7]; risk difference, 23% [95% CI of risk difference, 5%-40%]), pain management (34 of 36, 94% [95% CI, 81%-99%], versus 26 of 36, 72% [95% CI, 55%-86%], p=0

  19. Joint Attention in Autism: Teaching Smiling Coordinated with Gaze to Respond to Joint Attention Bids

    ERIC Educational Resources Information Center

    Krstovska-Guerrero, Ivana; Jones, Emily A.

    2013-01-01

    Children with autism demonstrate early deficits in joint attention and expressions of affect. Interventions to teach joint attention have addressed gaze behavior, gestures, and vocalizations, but have not specifically taught an expression of positive affect such as smiling that tends to occur during joint attention interactions. Intervention was…

  20. Sacroiliac joint tuberculosis: surgical management by posterior open-window focal debridement and joint fusion.

    PubMed

    Zhu, Guo; Jiang, Li-Yuan; Yi, Zhang; Ping, Li; Duan, Chun-Yue; Yong, Cao; Liu, Jin-Yang; Hu, Jian-Zhong

    2017-11-29

    Sacroiliac joint tuberculosis(SJT) is relatively uncommon, but it may cause severe sacroiliac joint destruction and functional disorder. Few studies in the literature have been presented on SJT, reports of surgical treatment for SJT are even fewer. In this study, we retrospectively reviewed surgical management of patients with severe SJT of 3 different types and proposed to reveal the clinical manifestations and features and aim to determine the efficiency and security of such surgical treatment. We reviewed 17 patients with severe SJT of 3 different types who underwent posterior open-window focal debridement and bone graft for joint fusion. Among them,five patients with anterior sacral abscess had anterior abscess curettage before debridement. Two patients with lumbar vertebral tuberculosis received one-stage posterior tuberculous debridement, interbody fusion and instrumentation. Follow-up was performed 36 months (26 to 45 months) using the following parameters: erythrocyte sedimentation rate(ESR), status of joint bony fusion on CT scan, visual analogue scale (VAS) and the Oswestry Disability Index (ODI). Buttock pain and low back pain were progressively relieved with time. 6 months later, pain was not obvious, and ESR resumed to normal levels within 3 months. Solid fusion of the sacroiliac joint occurred within 12 months in all cases. No complications or recurrence occurred. At final follow-up, all patients had no pain or only minimal discomfort over the affected joint and almost complete functional recovery. Posterior open-window focal debridement and joint fusion is an efficient and secure surgical method to treat severe SJT. If there is an abscess in the front of the sacroiliac joint, anterior abscess curettage should be performed as a supplement.

  1. Jointness for the Rest of Us: Reforming Joint Professional Development

    DTIC Science & Technology

    2016-06-10

    where service capabilities are combined to maximize effectiveness while minimizing vulnerabilities. However, despite the passage of thirty years ...staff of the Joint Advance Warfighting School and the Joint Forces Staff College for their support during the academic year . Special thanks to my...seminar faculty Colonel Chris Rogers, Dr. Mike Pavlec, and Captain Miguel “Boo” Peko for the lessons and laughs that have made this year so enjoyable

  2. [Sports participation after joint arthroplasty].

    PubMed

    Dauty, M; Letenneur, J

    2007-12-01

    To recommand sports activities after joint arthroplasty from the literature analysis, the French surgeon's opinion and wish patients. From the Medline data base interrogation according to keywords: Sports, Arthroplasty, Athletics, Physical training, two different readers, an orthopedic surgeon and a Physical Medicine and Rehabilitation physician selected articles in French or English language according to the level of proofs of the french classification of the Accreditation and Health Evaluation National Agency (Anaes). Professional practices were estimated by the interrogation of 30 orthopedic surgeons members of the french West Orthopaedics Society (SOO). The demand of sports practice was studied with patients recently operated for a primary total knee arthroplasty (TKA) after gonarthrosis. Twenty-two articles were selected from 305 articles obtained by the search according to keywords. Ten literature reviews are limited by the absence of prospective randomized study. A level II study and eleven level IV articles are reported. According to the subjective orthropedic surgeon's opinion, the objective results based on the joint load studied and the percentage of arthroplasty revision, sport is beneficial for the individual health but perhaps not for the arthroplasty survey. However, aerobic and leisure activities are recommended (walking, swimming, cycling) in agreement with the demand of the patients recently operated with a TKA. TKA differs from Total Hip Arthroplasty for jogging because of knee joint constraints during the knee flexion. A single study reports sports possibilities after shoulder arthroplasty and ankle arthroplasty and no study reports results after elbow arthroplasty.

  3. 25-Hydroxyvitamin D Concentration, Vitamin D Intake and Joint Symptoms in Postmenopausal Women

    PubMed Central

    Chlebowski, Rowan T.; Johnson, Karen C.; Lane, Dorothy; Pettinger, Mary; Kooperberg, Charles L.; Wactawski-Wende, Jean; Rohan, Tom; Jo O'Sullivan, Mary; Yasmeen, Shagufta; Hiatt, Robert A.; Shikany, James M.; Vitolins, Mara; Khandekar, Janu; Hubbell, F. Allan

    2010-01-01

    Introduction Low 25 hydroxyvitamin D (25(OH) D) concentrations have been associated with radiologic worsening of osteoarthritis in some reports. However, the results are mixed and few studies have evaluated associations between 25(OH) D concentrations and both total vitamin D intake and clinical joint symptoms. Study Design Cross-sectional analyses of information from a subset of 1993 postmenopausal women obtained at baseline entry in the Women's Health Initiative Calcium plus Vitamin D clinical trial. Main Outcome Measures 25(OH) D concentration, total vitamin D intake (diet plus supplements), presence and severity of joint pain and joint swelling. Results The 25(OH) D levels were commonly low with 53% having deficient (< 50 nmol/L) and only 17% having sufficient (> 72 nmol/L) levels. Joint pain (reported by 74%) and joint swelling (reported by 34%) were also commonly reported. 25(OH) D concentrations were modestly correlated with total vitamin D intake (R =0.29, P<0.0001); however, considerable variability in 25(OH) D concentrations for a given vitamin D intake was seen. In adjusted linear regression models, lower serum 25(OH) D concentrations were associated with higher average joint pain score (P=0.01 for trend) with differences most apparent in the lowest 25(OH) D levels sextile. Conclusions Relatively low 25(OH) D levels and a high frequency of joint symptoms were common in this population of postmenopausal women. Total vitamin D intake was only modestly associated with 25(OH) D. Low serum 25(OH) D concentrations were associated with higher joint pain scores. These findings can inform the design of future intervention trials. PMID:21093181

  4. 12 CFR 347.107 - Joint ventures.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Joint ventures. 347.107 Section 347.107 Banks... INTERNATIONAL BANKING § 347.107 Joint ventures. (a) Joint ventures. If a bank, directly or indirectly, acquires or holds an equity interest in a foreign organization that is a joint venture, and the bank or its...

  5. About the Joint Chiefs of Staff

    Science.gov Websites

    JCS: Search Home Media News Photos Videos Publications About The Joint Staff Chairman Vice Chairman J8 | Force Structure, Resources & Assessment Contact Joint Staff Structure Home : About About the Joint Chiefs of Staff Download the CJCS Historic Guide The Joint Chiefs of Staff consist of the Chairman

  6. Facet joint hypertrophy is a misnomer: A retrospective study.

    PubMed

    An, Sang Joon; Seo, Mi Sook; Choi, Soo Il; Lim, Tae-Ha; Shin, So Jin; Kang, Keum Nae; Kim, Young Uk

    2018-06-01

    One of the major causes of lumbar spinal canal stenosis (LSCS) has been considered facet joint hypertrophy (FJH). However, a previous study asserted that "FJH" is a misnomer because common facet joints are no smaller than degenerative facet joints; however, this hypothesis has not been effectively demonstrated. Therefore, in order to verify that FJH is a misnomer in patients with LSCS, we devised new morphological parameters that we called facet joint thickness (FJT) and facet joint cross-sectional area (FJA).We collected FJT and FJA data from 114 patients with LSCS. A total of 86 control subjects underwent lumbar magnetic resonance imaging (MRI) as part of routine medical examinations, and axial T2-weighted MRI images were obtained from all participants. We measured FJT by drawing a line along the facet area and then measuring the narrowest point at L4-L5. We measured FJA as the whole cross-sectional area of the facet joint at the stenotic L4-L5 level.The average FJT was 1.60 ± 0.36 mm in the control group and 1.11 ± 0.32 mm in the LSCS group. The average FJA was 14.46 ± 5.17 mm in the control group and 9.31 ± 3.47 mm in the LSCS group. Patients with LSCS had significantly lower FJTs (P < .001) and FJAs (P < .001).FJH, a misnomer, should be renamed facet joint area narrowing. Using this terminology would eliminate confusion in descriptions of the facet joint.

  7. 26 CFR 1.6015-1 - Relief from joint and several liability on a joint return.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... they claim losses attributable to H's limited partnership interest in Partnership A. In January 2006... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Relief from joint and several liability on a... joint and several liability on a joint return. (a) In general. (1) An individual who qualifies and...

  8. Large displacement spherical joint

    DOEpatents

    Bieg, Lothar F.; Benavides, Gilbert L.

    2002-01-01

    A new class of spherical joints has a very large accessible full cone angle, a property which is beneficial for a wide range of applications. Despite the large cone angles, these joints move freely without singularities.

  9. Does Success Of Arthroscopic Laser Surgery In The Knee Joint Warrant Its Extension To "Non-Knee" Joints?

    NASA Astrophysics Data System (ADS)

    Smith, Chadwick F.; Johansen, W. Edward; Vangness, C. Thomas; Yamaguchi, Ken; McEleney, Emmett T.; Bales, Peter

    1987-03-01

    One of the authors has performed 162 arthroscopic laser surgeries in the knee joint without any major complication. Other investigators have recently proposed diagnostic arthroscopy and arthroscopic surgery for "non-knee" joints. The authors have proposed that arthroscopic laser surgery he extended to "non-knee" joints. The authors have performed arthroscopic laser surgery on "non-knee" joints of twelve cadavers. One of the authors have performed one successful arthroscopic surgery on a shoulder joint with only a minor, transient complication of subcutaneous emphysema. Is laser arthroscopic surgery safe and effective in "non-knee" joints? The evolving answer appears to be a qualified "Yes," which needs to be verified by a multicenter trial.

  10. Estimation of Time-Varying, Intrinsic and Reflex Dynamic Joint Stiffness during Movement. Application to the Ankle Joint

    PubMed Central

    Guarín, Diego L.; Kearney, Robert E.

    2017-01-01

    Dynamic joint stiffness determines the relation between joint position and torque, and plays a vital role in the control of posture and movement. Dynamic joint stiffness can be quantified during quasi-stationary conditions using disturbance experiments, where small position perturbations are applied to the joint and the torque response is recorded. Dynamic joint stiffness is composed of intrinsic and reflex mechanisms that act and change together, so that nonlinear, mathematical models and specialized system identification techniques are necessary to estimate their relative contributions to overall joint stiffness. Quasi-stationary experiments have demonstrated that dynamic joint stiffness is heavily modulated by joint position and voluntary torque. Consequently, during movement, when joint position and torque change rapidly, dynamic joint stiffness will be Time-Varying (TV). This paper introduces a new method to quantify the TV intrinsic and reflex components of dynamic joint stiffness during movement. The algorithm combines ensemble and deterministic approaches for estimation of TV systems; and uses a TV, parallel-cascade, nonlinear system identification technique to separate overall dynamic joint stiffness into intrinsic and reflex components from position and torque records. Simulation studies of a stiffness model, whose parameters varied with time as is expected during walking, demonstrated that the new algorithm accurately tracked the changes in dynamic joint stiffness using as little as 40 gait cycles. The method was also used to estimate the intrinsic and reflex dynamic ankle stiffness from an experiment with a healthy subject during which ankle movements were imposed while the subject maintained a constant muscle contraction. The method identified TV stiffness model parameters that predicted the measured torque very well, accounting for more than 95% of its variance. Moreover, both intrinsic and reflex dynamic stiffness were heavily modulated through the

  11. Hospital Discharge Within 1 Day After Total Joint Arthroplasty From a Veterans Affairs Hospital Does Not Increase Complication and Readmission Rates.

    PubMed

    Kiskaddon, Eric M; Lee, Jessica H; Meeks, Brett D; Barnhill, Spencer W; Froehle, Andrew W; Krishnamurthy, Anil

    2018-05-01

    Attempts to control costs associated with total joint arthroplasty have included efforts to shorten hospital length of stay (LOS). Concerns related to patient outcomes and safety with decreased LOS persist. The purpose of this study was to investigate whether discharge on postoperative day (POD) 1 after joint replacement is associated with increased rates of 90-day return to the operating room, and 30-day readmissions and emergency department (ED) visits. After chart review, 447 patients admitted between January 2, 2013 and September 16, 2016 met inclusion criteria. All patients underwent one total joint arthroplasty. Patients were either discharged on POD 1 (subgroup 1) or POD 2 or 3 (subgroup 2). Statistical evaluation was performed using Wilcoxon-Mann-Whitney tests for continuous variables, and Fisher exact tests for categorical and frequency data. Statistical significance was established at P ≤ .05. Subgroup 1 had significantly fewer return trips to the operating room (P = .043) and significantly fewer 30-day readmissions (P = .033). ED visits were not significantly different between groups (P = .901). Early discharge after joint arthroplasty appears to be a viable practice and did not result in increased rates of reoperation within the 90-day global period, or rates of 30-day readmission and ED visits. Our results support the utilization of an early discharge protocol on POD 1, with no evidence that shorter LOS results in higher rates of short-term complications. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Hip and knee joints are more stabilized than driven during the stance phase of gait: an analysis of the 3D angle between joint moment and joint angular velocity.

    PubMed

    Dumas, R; Cheze, L

    2008-08-01

    Joint power is commonly used in orthopaedics, ergonomics or sports analysis but its clinical interpretation remains controversial. Some basic principles on muscle actions and energy transfer have been proposed in 2D. The decomposition of power on 3 axes, although questionable, allows the same analysis in 3D. However, these basic principles have been widely criticized, mainly because bi-articular muscles must be considered. This requires a more complex computation in order to determine how the individual muscle force contributes to drive the joint. Conversely, with simple 3D inverse dynamics, the analysis of both joint moment and angular velocity directions is essential to clarify when the joint moment can contribute or not to drive the joint. The present study evaluates the 3D angle between the joint moment and the joint angular velocity and investigates when the hip, knee and ankle joints are predominantly driven (angle close to 0 degrees and 180 degrees ) or stabilized (angle close to 90 degrees ) during gait. The 3D angle curves show that the three joints are never fully but only partially driven and that the hip and knee joints are mainly stabilized during the stance phase. The notion of stabilization should be further investigated, especially for subjects with motion disorders or prostheses.

  13. Swivel Joint For Liquid Nitrogen

    NASA Technical Reports Server (NTRS)

    Milner, James F.

    1988-01-01

    Swivel joint allows liquid-nitrogen pipe to rotate through angle of 100 degree with respect to mating pipe. Functions without cracking hard foam insulation on lines. Pipe joint rotates on disks so mechanical stress not transmitted to thick insulation on pipes. Inner disks ride on fixed outer disks. Disks help to seal pressurized liquid nitrogen flowing through joint.

  14. The Standard Joint Unit.

    PubMed

    Casajuana Kögel, Cristina; Balcells-Olivero, María Mercedes; López-Pelayo, Hugo; Miquel, Laia; Teixidó, Lídia; Colom, Joan; Nutt, David John; Rehm, Jürgen; Gual, Antoni

    2017-07-01

    Reliable data on cannabis quantities is required to improve assessment of cannabis consumption for epidemiological analysis and clinical assessment, consequently a Standard Joint Unit (SJU) based on quantity of 9-Tetrahydrocannabinol (9-THC) has been established. Naturalistic study of a convenience sample recruited from February 2015-June 2016 in universities, leisure spaces, mental health services and cannabis clubs in Barcelona. Adults, reporting cannabis use in the last 60 days, without cognitive impairment or language barriers, answered a questionnaire on cannabis use and were asked to donate a joint to further determine their 9-THC and Cannabidiol (CBD) content. 492 participants donated 315 valid joints. Donators were on average 29 years old, mostly men (77%), single (75%), with at least secondary studies (73%) and in active employment (63%). Marijuana joints (N=232) contained a median of 6.56mg of 9-THC (Interquartile range-IQR=10,22) and 0.02mg of CBD (IQR=0.02); hashish joints (N=83) a median of 7.94mg of 9-THC (IQR=10,61) and 3.24mg of CBD (IQR=3.21). Participants rolled 4 joints per gram of cannabis and paid 5€ per gram (median values). Consistent 9-THC-content in joints lead to a SJU of 7mg of 9-THC, the integer number closest to the median values shared by both cannabis types. Independently if marijuana or hashish, 1 SJU = 1 joint = 0.25 g of cannabis = 7 mg of 9-THC. For CBD, only hashish SJU contained relevant levels. Similarly to the Standard Drink Unit for alcohol, the SJU is useful for clinical, epidemiological and research purposes. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Temporo mandibular joint ankylosis.

    PubMed

    Vasconcelos, Belmiro Cavalcanti do Egito; Porto, Gabriela Granja; Bessa-Nogueira, Ricardo Viana

    2008-01-01

    Ankylosis may be defined as joint surfaces fusion. The treatment of temporomandibular joint ankylosis poses a significant challenge because of the high recurrence rate. The aim of this study is to report six cases treated by joint reconstruction, evaluate the results of these surgeries and review the literature. The sample in this retrospective study was obtained from the records of the university hospital, patients who had to undergo ankylosis treatment by alloplastic or autogenous graft between March 2001 and October 2005. Pre - and post-operative assessment included a throughout history and physical examination to determine the cause of ankylosis, the Maximum mouth opening (MMO), etiology and type of ankylosis, recurrence rate and presence of facial nerve paralysis. The mean MMO in the pre-operative period was 9.6 mm (0 mm to 17 mm) and in the post-operative period it was of 31.33 mm (14 mm to 41 mm), there was no facial nerve paralysis and there was recurrence in just one case. The joint reconstruction with alloplastic or autogenous grafts for the ankylosis treatment proved to be efficient in relation to the post-operative MMO, recurrence and joint function.

  16. Minimally invasive arthrodesis for chronic sacroiliac joint dysfunction using the SImmetry SI Joint Fusion system.

    PubMed

    Miller, Larry E; Block, Jon E

    2014-01-01

    Chronic sacroiliac (SI) joint-related low back pain (LBP) is a common, yet under-diagnosed and undertreated condition due to difficulties in accurate diagnosis and highly variable treatment practices. In patients with debilitating SI-related LBP for at least 6 months duration who have failed conservative management, arthrodesis is a viable option. The SImmetry(®) SI Joint Fusion System is a novel therapy for SI joint fusion, not just fixation, which utilizes a minimally invasive surgical approach, instrumented fixation for immediate stability, and joint preparation with bone grafting for a secure construct in the long term. The purpose of this report is to describe the minimally invasive SI Joint Fusion System, including patient selection criteria, implant characteristics, surgical technique, postoperative recovery, and biomechanical testing results. Advantages and limitations of this system will be discussed.

  17. Unloading joints to treat osteoarthritis, including joint distraction.

    PubMed

    Lafeber, Floris P J G; Intema, Femke; Van Roermund, Peter M; Marijnissen, Anne C A

    2006-09-01

    Patients are increasingly becoming interested in nonpharmacologic approaches to manage their osteoarthritis. This review examines the recent literature on the potential beneficial effects of unloading joints in the treatment of osteoarthritis, with a focus on joint distraction. Mechanical factors are involved in the development and progression of osteoarthritis. If "loading" is a major cause in development and progression of osteoarthritis, then "unloading" may be able to prevent progression. There is evidence that unloading may be effective in reducing pain and slowing down structural damage. This review describes unloading by footwear and bracing (nonsurgical), unloading by osteotomy (surgical), and has a focus on unloading by joint distraction. Excellent reviews in all these three fields have been published over the past few years. Recent studies argue for the usefulness of a biomechanical approach to improve function and possibly reduce disease progression in osteoarthritis. To improve patient function and possibly reduce disease progression, a biomechanical approach should be considered in treating patients with osteoarthritis. Further research (appropriate high-quality clinical trials) and analysis (clinical as well as preclinical and fundamental) are still necessary, however, to understand, validate, and refine the different approaches of unloading to treat osteoarthritis.

  18. Joint design of QC-LDPC codes for coded cooperation system with joint iterative decoding

    NASA Astrophysics Data System (ADS)

    Zhang, Shunwai; Yang, Fengfan; Tang, Lei; Ejaz, Saqib; Luo, Lin; Maharaj, B. T.

    2016-03-01

    In this paper, we investigate joint design of quasi-cyclic low-density-parity-check (QC-LDPC) codes for coded cooperation system with joint iterative decoding in the destination. First, QC-LDPC codes based on the base matrix and exponent matrix are introduced, and then we describe two types of girth-4 cycles in QC-LDPC codes employed by the source and relay. In the equivalent parity-check matrix corresponding to the jointly designed QC-LDPC codes employed by the source and relay, all girth-4 cycles including both type I and type II are cancelled. Theoretical analysis and numerical simulations show that the jointly designed QC-LDPC coded cooperation well combines cooperation gain and channel coding gain, and outperforms the coded non-cooperation under the same conditions. Furthermore, the bit error rate performance of the coded cooperation employing jointly designed QC-LDPC codes is better than those of random LDPC codes and separately designed QC-LDPC codes over AWGN channels.

  19. [Meniscoids of the intervertebral joints].

    PubMed

    Kos, J; Hert, J; Sevcík, P

    2002-01-01

    A large amount of material was used to study the distribution, location and shape of meniscoids in intervertebral joints of the human spine, from the atlanto-occipital joint to the sacrum, in order to find out how many of intervertebral joints had mobile meniscoids. These might be regarded as possible causes of spinal blockade or other vertebrogenous complaints. The materials provided by the Department of Anatomy and Department of Forensic Medicine at the Faculty of Medicine of Charles University in Pilznen included 20 cadaverous spines from humans aged 20 to 80 years. Access to each joint was provided by dissection of the articular capsule from the lower articular processes of the vertebra situated above. In the orthograde view, all meniscoids were described in terms of shape, size, consistence and location. Their structure was ascertained by histological examination of cross sections stained with haematoxylin and eosin. Meniscoids varying in shape and size were found in all of the intervertebral joints. They were classified by their histological structure as synovial, fat and fibrous meniscoids. The first category was observed frequently, the last only rarely. A total of 29 mobile meniscoids were recorded, most of them in the lumbar spine. Most of the meniscoids present in the cervical spine were of synovial and less frequently of fat types. Meniscoids found in the thoracic spine were poorly developed synovial ones and those present in the lumbar spine were of all types and were also largest in size. The most conspicuous meniscoids were seen in the spines that showed degenerative changes in intervertebral joints. Large fat pads were found in atlanto-occipital and atlanto-axial joints. Mobile meniscoids, most of them present in the lumbar spine (6.4% of all joints.), were connected with the capsule by a thin pedicle and it was possible to move them over a half of the articular surface. Some inter-individual changes were also found; in some spines, the most

  20. Recent Advances in Computational Mechanics of the Human Knee Joint

    PubMed Central

    Kazemi, M.; Dabiri, Y.; Li, L. P.

    2013-01-01

    Computational mechanics has been advanced in every area of orthopedic biomechanics. The objective of this paper is to provide a general review of the computational models used in the analysis of the mechanical function of the knee joint in different loading and pathological conditions. Major review articles published in related areas are summarized first. The constitutive models for soft tissues of the knee are briefly discussed to facilitate understanding the joint modeling. A detailed review of the tibiofemoral joint models is presented thereafter. The geometry reconstruction procedures as well as some critical issues in finite element modeling are also discussed. Computational modeling can be a reliable and effective method for the study of mechanical behavior of the knee joint, if the model is constructed correctly. Single-phase material models have been used to predict the instantaneous load response for the healthy knees and repaired joints, such as total and partial meniscectomies, ACL and PCL reconstructions, and joint replacements. Recently, poromechanical models accounting for fluid pressurization in soft tissues have been proposed to study the viscoelastic response of the healthy and impaired knee joints. While the constitutive modeling has been considerably advanced at the tissue level, many challenges still exist in applying a good material model to three-dimensional joint simulations. A complete model validation at the joint level seems impossible presently, because only simple data can be obtained experimentally. Therefore, model validation may be concentrated on the constitutive laws using multiple mechanical tests of the tissues. Extensive model verifications at the joint level are still crucial for the accuracy of the modeling. PMID:23509602

  1. The joint venture alternative to mergers.

    PubMed

    Enders, R J

    1995-02-01

    However, while a joint venture may be "safe" from antitrust challenge, it is not without some practical difficulties, especially with respect to consolidating services at one location or jointly offering services provided at multiple facilities. These practical concerns include: 1. Who will exercise operational management of the joint venture? 2. How will the joint venture deal with different pricing for services that will be provided at multiple locations? 3. What criteria will be used to decide the location at which consolidated tertiary services will be offered? 4. In what circumstances can the joint venture be unwound, either in its entirety or as to discrete functions? When clinical services have been consolidated at one location, there is an appropriate concern by the other hospital that it will be unable to provide or re-enter the market for those services if the joint venture dissolves. These operational concerns, of course, are not addressed in the Consent Decree. Thus, even if a joint venture relationship survives antitrust scrutiny, the parties must still negotiate and resolve these operational issues in order for the joint venture to be viable.

  2. Innervation of the Anterior Sacroiliac Joint.

    PubMed

    Cox, Marcus; Ng, Garrett; Mashriqi, Faizullah; Iwanaga, Joe; Alonso, Fernando; Tubbs, Kevin; Loukas, Marios; Oskouian, Rod J; Tubbs, R Shane

    2017-11-01

    Sacroiliac joint pain can be disabling and recalcitrant to medical therapy. The innervation of this joint is poorly understood, especially its anterior aspect. Therefore, the present cadaveric study was performed to better elucidate this anatomy. Twenty-four cadaveric sides underwent dissection of the anterior sacroiliac joint, with special attention given to any branches from regional nerves to this joint. No femoral, obturator, or lumbosacral trunk branches destined to the anterior sacroiliac joint were identified in the 24 sides. In 20 sides, one or two small branches (less than 0.5 mm in diameter) were found to arise from the L4 ventral ramus (10%), the L5 ventral ramus (80%), or simultaneously from both the L4 and L5 ventral rami (10%). The length of the branches ranged from 5 to 31 mm (mean, 14 mm). All these branches arose from the posterior part of the nerves and traveled to the anterior surface of the sacroiliac joint. No statistical significance was found between sides or sexes. An improved knowledge of the innervation of the anterior sacroiliac joint might decrease suffering in patients with chronic sacroiliac joint pain. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Bolted joints in graphite-epoxy composites

    NASA Technical Reports Server (NTRS)

    Hart-Smith, L. J.

    1976-01-01

    All-graphite/epoxy laminates and hybrid graphite-glass/epoxy laminates were tested. The tests encompassed a range of geometries for each laminate pattern to cover the three basic failure modes - net section tension failure through the bolt hole, bearing and shearout. Static tensile and compressive loads were applied. A constant bolt diameter of 6.35 mm (0.25 in.) was used in the tests. The interaction of stress concentrations associated with multi-row bolted joints was investigated by testing single- and double-row bolted joints and open-hole specimens in tension. For tension loading, linear interaction was found to exist between the bearing stress reacted at a given bolt hole and the remaining tension stress running by that hole to be reacted elsewhere. The interaction under compressive loading was found to be non-linear. Comparative tests were run using single-lap bolted joints and double-lap joints with pin connection. Both of these joint types exhibited lower strengths than were demonstrated by the corresponding double-lap joints. The analysis methods developed here for single bolt joints are shown to be capable of predicting the behavior of multi-row joints.

  4. Chromium content in the human hip joint tissues.

    PubMed

    Brodziak-Dopierała, Barbara; Kwapuliński, Jerzy; Sobczyk, Krzysztof; Wiechuła, Danuta

    2015-02-01

    Chromium has many important functions in the human body. For the osseous tissue, its role has not been clearly defined. This study was aimed at determining chromium content in hip joint tissues. A total of 91 hip joint samples were taken in this study, including 66 from females and 25 from males. The sample tissues were separated according to their anatomical parts. The chromium content was determined by the AAS method. The statistical analysis was performed with U Mann-Whitney's non-parametric test, P≤0.05. The overall chromium content in tissues of the hip joint in the study subjects was as follows: 5.73 µg/g in the articular cartilage, 5.33 µg/g in the cortical bone, 17.86 µg/g in the cancellous bone, 5.95 µg/g in the fragment of the cancellous bone from the intertrochanteric region, and 1.28 µg/g in the joint capsule. The chromium contents were observed in 2 group patients, it was 7.04 µg/g in people with osteoarthritis and 12.59 µg/g in people with fractures. The observed chromium content was highest in the cancellous bone and the lowest in the joint capsule. Chromium content was significantly different between the people with hip joint osteoarthritis and the people with femoral neck fractures. Copyright © 2015 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  5. Space Station alpha joint bearing

    NASA Technical Reports Server (NTRS)

    Everman, Michael R.; Jones, P. Alan; Spencer, Porter A.

    1987-01-01

    Perhaps the most critical structural system aboard the Space Station is the Solar Alpha Rotary Joint which helps align the power generation system with the sun. The joint must provide structural support and controlled rotation to the outboard transverse booms as well as power and data transfer across the joint. The Solar Alpha Rotary Joint is composed of two transition sections and an integral, large diameter bearing. Alpha joint bearing design presents a particularly interesting problem because of its large size and need for high reliability, stiffness, and on orbit maintability. The discrete roller bearing developed is a novel refinement to cam follower technology. It offers thermal compensation and ease of on-orbit maintenance that are not found in conventional rolling element bearings. How the bearing design evolved is summarized. Driving requirements are reviewed, alternative concepts assessed, and the selected design is described.

  6. [Application of joint reconstruction with autogenous coronoid process graft to treat temporomandibular joint ankylosis].

    PubMed

    Xie, Qing-tiao; Huang, Xuan-ping; Jiang, Xian-fang; Yang, Yuan-yuan; Li, Hua; Lin, Xi

    2013-08-01

    To evaluate the clinical effect of joint reconstruction by using autogenous coronoid process graft to treat temporomandibular joint(TMJ) ankylosis. Nine cases of TMJ ankylosis from September 2008 to September 2010 were surgically treated by joint reconstruction with autogenous coronoid process graft, using autogenous articular disc or prosthodontic membrane as interpositional material. Mouth opening, occlusion and cone beam CT(CBCT) were used for evaluation before and after surgery. Satisfactory mouth opening was achieved in all patients and no one got occlusal changes or reankylosis during follow-up. CBCT showed that coronoid process graft reached bone union with the ramus and turned to be round. It is effective to cure TMJ ankylosis through joint reconstruction with autogenous coronoid process graft.

  7. Cost analysis of debridement and retention for management of prosthetic joint infection.

    PubMed

    Peel, T N; Dowsey, M M; Buising, K L; Liew, D; Choong, P F M

    2013-02-01

    Prosthetic joint infection remains one of the most devastating complications of arthroplasty. Debridement and retention of the prosthesis is an attractive management option in carefully selected patients. Despite this, there are no data investigating the cost of this management modality for prosthetic joint infections. The aim of this case-control study was to calculate the cost associated with debridement and retention for management of prosthetic joint infection compared with primary joint replacement surgery without prosthetic joint infection. From 1 January 2008 to 30 June 2010, there were 21 prosthetic joint infections matched to 42 control patients. Controls were matched to cases according to the arthroplasty site, age and sex. Cases had a greater number of unplanned readmissions (100% vs. 7.1%; p <0.001), more additional surgery (3.3 vs. 0.07; p <0.001) and longer total bed days (31.6 vs. 7.9 days; p <0.001). In addition they had more inpatient, outpatient and emergency department visits (p <0.001, respectively). For patients with prosthetic joint infection the total cost, including index operation and costs of management of the prosthetic joint infection, was 3.1 times the cost of primary arthoplasty; the mean cost for cases was Australian dollars (AUD) $69,414 (±29,869) compared with $22,085 (±8147) (p <0.001). The demand for arthroplasty continues to grow and with that, the number of prosthetic joint infections will also increase, placing significant burden on the health system. Our study adds significantly to the growing body of evidence highlighting the substantial costs associated with prosthetic joint infection. © 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.

  8. Phase 1 Program Joint Report

    NASA Technical Reports Server (NTRS)

    Nield, George C. (Editor); Vorobiev, Pavel Mikhailovich (Editor)

    1999-01-01

    This report consists of inputs from each of the Phase I Program Joint Working Groups. The Working Groups were tasked to describe the organizational structure and work processes that they used during the program, joint accomplishments, lessons learned, and applications to the International Space Station Program. This report is a top-level joint reference document that contains information of interest to both countries.

  9. Self-Alining Quick-Connect Joint

    NASA Technical Reports Server (NTRS)

    Lucy, M. H.

    1983-01-01

    Quick connect tapered joint used with minimum manipulation and force. Split ring retainer holds locking ring in place. Minimal force required to position male in female joint, at which time split-ring retainers are triggered to release split locking rings. Originally developed to assemble large space structures, joint is simple, compact, strong, lightweight, self alining, and has no loose parts.

  10. Feature-extracted joint transform correlation.

    PubMed

    Alam, M S

    1995-12-10

    A new technique for real-time optical character recognition that uses a joint transform correlator is proposed. This technique employs feature-extracted patterns for the reference image to detect a wide range of characters in one step. The proposed technique significantly enhances the processing speed when compared with the presently available joint transform correlator architectures and shows feasibility for multichannel joint transform correlation.

  11. Cancer risk among patients with finger and hand joint and temporo-mandibular joint prostheses in Denmark.

    PubMed

    Fryzek, J P; Mellemkjaer, L; McLaughlin, J K; Blot, W J; Olsen, J H

    1999-05-31

    The use of artificial joint implants has risen greatly over the past years. However, few investigations of the cancer risk associated with implants have been performed. We investigated cancer risk in patients with finger and hand joint and temporo-mandibular (TMJ) joint implants. A nationwide cohort in Denmark of patients with finger and hand joint prostheses (n = 858) or TMJ implants (n = 389) was followed from January 1, 1977, to December 31, 1995, to evaluate any potential cancer risks subsequent to receiving these implants. Standardized incidence ratios (SIRs) for all cancers were 1.0 (95% CI = 0.8-1.2) for the finger and hand joint cohort and 1.1 (95% CI = 0.8-1.7) for the TMJ cohort. A significant risk for non-Hodgkin's lymphoma was found in the finger and hand joint cohort (SIR = 3.8, 95% CI = 1.5-7.8). When the finger and hand joint cohort was stratified by diagnosis of rheumatoid arthritis, the excess risk was seen only in the group with rheumatoid arthritis. This is consistent with past studies, which have found an association between rheumatoid arthritis and non-Hodgkin's lymphoma. Our results provide evidence that the cancer risk for patients with finger and hand joint prostheses and TMJ implants is similar to that for the general population.

  12. JointMMCC: Joint Maximum-Margin Classification and Clustering of Imaging Data

    PubMed Central

    Filipovych, Roman; Resnick, Susan M.; Davatzikos, Christos

    2012-01-01

    A number of conditions are characterized by pathologies that form continuous or nearly-continuous spectra spanning from the absence of pathology to very pronounced pathological changes (e.g., normal aging, Mild Cognitive Impairment, Alzheimer's). Moreover, diseases are often highly heterogeneous with a number of diagnostic subcategories or subconditions lying within the spectra (e.g., Autism Spectrum Disorder, schizophrenia). Discovering coherent subpopulations of subjects within the spectrum of pathological changes may further our understanding of diseases, and potentially identify subconditions that require alternative or modified treatment options. In this paper, we propose an approach that aims at identifying coherent subpopulations with respect to the underlying MRI in the scenario where the condition is heterogeneous and pathological changes form a continuous spectrum. We describe a Joint Maximum-Margin Classification and Clustering (JointMMCC) approach that jointly detects the pathologic population via semi-supervised classification, as well as disentangles heterogeneity of the pathological cohort by solving a clustering subproblem. We propose an efficient solution to the non-convex optimization problem associated with JointMMCC. We apply our proposed approach to an MRI study of aging, and identify coherent subpopulations (i.e., clusters) of cognitively less stable adults. PMID:22328179

  13. Proximal Versus Distal Control of Two-Joint Planar Reaching Movements in the Presence of Neuromuscular Noise

    PubMed Central

    Nguyen, Hung P.; Dingwell, Jonathan B.

    2012-01-01

    Determining how the human nervous system contends with neuro-motor noise is vital to understanding how humans achieve accurate goal-directed movements. Experimentally, people learning skilled tasks tend to reduce variability in distal joint movements more than in proximal joint movements. This suggests that they might be imposing greater control over distal joints than proximal joints. However, the reasons for this remain unclear, largely because it is not experimentally possible to directly manipulate either the noise or the control at each joint independently. Therefore, this study used a 2 degree-of-freedom torque driven arm model to determine how different combinations of noise and/or control independently applied at each joint affected the reaching accuracy and the total work required to make the movement. Signal-dependent noise was simultaneously and independently added to the shoulder and elbow torques to induce endpoint errors during planar reaching. Feedback control was then applied, independently and jointly, at each joint to reduce endpoint error due to the added neuromuscular noise. Movement direction and the inertia distribution along the arm were varied to quantify how these biomechanical variations affected the system performance. Endpoint error and total net work were computed as dependent measures. When each joint was independently subjected to noise in the absence of control, endpoint errors were more sensitive to distal (elbow) noise than to proximal (shoulder) noise for nearly all combinations of reaching direction and inertia ratio. The effects of distal noise on endpoint errors were more pronounced when inertia was distributed more toward the forearm. In contrast, the total net work decreased as mass was shifted to the upper arm for reaching movements in all directions. When noise was present at both joints and joint control was implemented, controlling the distal joint alone reduced endpoint errors more than controlling the proximal joint

  14. Proximal versus distal control of two-joint planar reaching movements in the presence of neuromuscular noise.

    PubMed

    Nguyen, Hung P; Dingwell, Jonathan B

    2012-06-01

    Determining how the human nervous system contends with neuro-motor noise is vital to understanding how humans achieve accurate goal-directed movements. Experimentally, people learning skilled tasks tend to reduce variability in distal joint movements more than in proximal joint movements. This suggests that they might be imposing greater control over distal joints than proximal joints. However, the reasons for this remain unclear, largely because it is not experimentally possible to directly manipulate either the noise or the control at each joint independently. Therefore, this study used a 2 degree-of-freedom torque driven arm model to determine how different combinations of noise and/or control independently applied at each joint affected the reaching accuracy and the total work required to make the movement. Signal-dependent noise was simultaneously and independently added to the shoulder and elbow torques to induce endpoint errors during planar reaching. Feedback control was then applied, independently and jointly, at each joint to reduce endpoint error due to the added neuromuscular noise. Movement direction and the inertia distribution along the arm were varied to quantify how these biomechanical variations affected the system performance. Endpoint error and total net work were computed as dependent measures. When each joint was independently subjected to noise in the absence of control, endpoint errors were more sensitive to distal (elbow) noise than to proximal (shoulder) noise for nearly all combinations of reaching direction and inertia ratio. The effects of distal noise on endpoint errors were more pronounced when inertia was distributed more toward the forearm. In contrast, the total net work decreased as mass was shifted to the upper arm for reaching movements in all directions. When noise was present at both joints and joint control was implemented, controlling the distal joint alone reduced endpoint errors more than controlling the proximal joint

  15. Minimally invasive arthrodesis for chronic sacroiliac joint dysfunction using the SImmetry SI Joint Fusion system

    PubMed Central

    Miller, Larry E; Block, Jon E

    2014-01-01

    Chronic sacroiliac (SI) joint-related low back pain (LBP) is a common, yet under-diagnosed and undertreated condition due to difficulties in accurate diagnosis and highly variable treatment practices. In patients with debilitating SI-related LBP for at least 6 months duration who have failed conservative management, arthrodesis is a viable option. The SImmetry® SI Joint Fusion System is a novel therapy for SI joint fusion, not just fixation, which utilizes a minimally invasive surgical approach, instrumented fixation for immediate stability, and joint preparation with bone grafting for a secure construct in the long term. The purpose of this report is to describe the minimally invasive SI Joint Fusion System, including patient selection criteria, implant characteristics, surgical technique, postoperative recovery, and biomechanical testing results. Advantages and limitations of this system will be discussed. PMID:24851059

  16. Functionally deficient mesenchymal stem cells reside in the bone marrow niche with M2-macrophages and amyloid-β protein adjacent to loose total joint implants.

    PubMed

    Margulies, Bryan S; DeBoyace, Sean D; Parsons, Adrienne M; Policastro, Connor G; Ee, Jessica S S; Damron, Timothy S

    2015-05-01

    We sought to demonstrate whether there is a difference in the local mesenchymal stem cells (MSC) niche obtained from patients undergoing their first total joint replacement surgery versus those patients undergoing a revision surgery for an failing total joint implant. Bone marrow aspirates collected from patients undergoing revision total joint arthroplasty were observed to be less clonal and the expression of PDGFRα, CD51, ALCAM, endoglin, CXCL12, nestin, and nucleostemin were decreased. Revision MSC were also less able to commit to an osteoblast-lineage or an adipocyte-lineage. Further, in revision MSC, OPG, and IL6 expression were increased. Monocytes, derived from revision whole marrow aspirates, were less capable of differentiating into osteoclasts, the cells implicated in the pathologic degradation of bone. Osteoclasts were also not observed in tissue samples collected adjacent to the implants of revision patients; however, the alternatatively activated M2-macrophage phenotype was observed in parallel with pathologic accumulations of amyloid-β, τ-protien and 3-nitrotyrosine. Despite the limited numbers of patients examined, our data suggest that nucleostemin may be a useful functional marker for MSC while the observation of M2-macrophage infiltration around the implant lays the foundation for future investigation into a novel mechanism that we propose is associated with loose total joint implants. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  17. HMA Longitudinal Joint Evaluation and Construction

    DOT National Transportation Integrated Search

    2011-02-01

    Longitudinal joint quality is essential to the successful performance of asphalt pavements. A number of states have begun to implement longitudinal joint specifications, and most are based on determinations of density. However, distress at the joint ...

  18. The volume of the human knee joint.

    PubMed

    Matziolis, Georg; Roehner, Eric; Windisch, Christoph; Wagner, Andreas

    2015-10-01

    Despite its clinical relevance, particularly in septic knee surgery, the volume of the human knee joint has not been established to date. Therefore, the objective of this study was to determine knee joint volume and whether or not it is dependent on sex or body height. Sixty-one consecutive patients (joints) who were due to undergo endoprosthetic joint replacement were enrolled in this prospective study. During the operation, the joint volume was determined by injecting saline solution until a pressure of 200 mmHg was achieved in the joint. The average volume of all knee joints was 131 ± 53 (40-290) ml. The volume was not found to be dependent on sex, but it was dependent on the patients' height (R = 0.312, p = 0.014). This enabled an estimation of the joint volume according to V = 1.6 height - 135. The considerable inter-individual variance of the knee joint volume would suggest that it should be determined or at least estimated according to body height if the joint volume has consequences for the diagnostics or therapy of knee disorders.

  19. Method of forming a joint

    DOEpatents

    Butt, Darryl Paul; Cutler, Raymond Ashton; Rynders, Steven Walton; Carolan, Michael Francis

    2006-08-22

    A method of joining at least two sintered bodies to form a composite structure, including providing a first multicomponent metallic oxide having a perovskitic or fluorite crystal structure; providing a second sintered body including a second multicomponent metallic oxide having a crystal structure of the same type as the first; and providing at an interface a joint material containing at least one metal oxide containing at least one metal identically contained in at least one of the first and second multicomponent metallic oxides. The joint material is free of cations of Si, Ge, Sn, Pb, P and Te and has a melting point below the sintering temperatures of both sintered bodies. The joint material is heated to a temperature above the melting point of the metal oxide(s) and below the sintering temperatures of the sintered bodies to form the joint. Structures containing such joints are also disclosed.

  20. RSRM Nozzle-to-Case Joint J-leg Development

    NASA Technical Reports Server (NTRS)

    Albrechtsen, Kevin U.; Eddy, Norman F.; Ewing, Mark E.; McGuire, John R.

    2003-01-01

    Since the beginning of the Space Shuttle Reusable Solid Rocket Motor (RSRM) program, nozzle-to-case joint polysulfide adhesive gas paths have occurred on several flight motors. These gas paths have allowed hot motor gases to reach the wiper O-ring. Even though these motors continue to fly safely with this condition, a desire was to reduce such occurrences. The RSRM currently uses a J-leg joint configuration on case field joints and igniter inner and outer joints. The J-leg joint configuration has been successfully demonstrated on numerous RSRM flight and static test motors, eliminating hot gas intrusion to the critical O-ring seals on these joints. Using the proven technology demonstrated on the case field joints and igniter joints, a nozzle-to-case joint J-leg design was developed for implementation on RSRM flight motors. This configuration provides an interference fit with nozzle fixed housing phenolics at assembly, with a series of pressurization gaps incorporated outboard of the joint mating surface to aid in joint pressurization and to eliminate any circumferential flow in this region. The joint insulation is bonded to the nozzle phenolics using the same pressure sensitive adhesive used in the case field joints and igniter joints. An enhancement to the nozzle-to-case joint J-leg configuration is the implementation of a carbon rope thermal barrier. The thermal barrier is located downstream of the joint bondline and is positioned within the joint in a manner where any hot gas intrusion into the joint passes through the thermal barrier, reducing gas temperatures to a level that would not affect O-rings downstream of the thermal barrier. This paper discusses the processes used in reaching a final nozzle-to-case joint J-leg design, provides structural and thermal results in support of the design, and identifies fabrication techniques and demonstrations used in arriving at the final configuration.

  1. Development and application of biomimetic electrospun nanofibers in total joint replacement

    NASA Astrophysics Data System (ADS)

    Song, Wei

    Failure of osseointegration (direct anchorage of an implant by bone formation at the bone-implant surface) and implant infection (such as that caused by Staphylococcus aureus, S. aureus) are the two main causes of implant failure and loosening. There is a critical need for orthopedic implants that promote rapid osseointegration and prevent bacterial colonization, particularly when placed in bone compromised by disease or physiology of the patients. A better understanding of the key factors that influence cell fate decisions at the bone-implant interface is required. Our study is to develop a class of "bone-like" nanofibers (NFs) that promote osseointegration while preventing bacterial colonization and subsequent infections. This research goal is supported by our preliminary data on the preparation of coaxial electrospun NFs composed of polycaprolactone (PCL) and polyvinyl alcohol (PVA) polymers arranged in a core-sheath shape. The PCL/PVA NFs are biocompatible and biodegradable with appropriate fiber diameter, pore size and mechanical strength, leading to enhanced cell adhesion, proliferation and differentiation of osteoblast precursor cells. The objective is to develop functionalized "bone-like" PCL/PVA NFs matrix embedded with antibiotics (doxycycline (Doxy), bactericidal and anti-osteoclastic) on prosthesis surface. Through a rat tibia implantation model, the Doxy incorporated coaxial NFs has demonstrated excellent in promoting osseointegration and bacteria inhibitory efficacy. NFs coatings significantly enhanced the bonding between implant and bone remodeling within 8 weeks. The SA-induced osteomyelitis was prevented by the sustained release of Doxy from NFs. The capability of embedding numerous bio-components including proteins, growth factors, drugs, etc. enables NFs an effective solution to overcome the current challenged issue in Total joint replacement. In summary, we proposed PCL/PVA electrospun nanofibers as promising biomaterials that can be applied on

  2. Rotary Joints With Electrical Connections

    NASA Technical Reports Server (NTRS)

    Osborn, F. W.

    1986-01-01

    Power and data transmitted on many channels. Two different rotary joints equipped with electrical connections between rotating and stationary parts. One joint transmits axial thrust and serves as interface between spinning and nonspinning parts of Galileo spacecraft. Other is scanning (limitedrotation) joint that aims scientific instruments from nonspinning part. Selected features of both useful to designers of robots, advanced production equipment, and remotely controlled instruments.

  3. Prosthetic Joint Infections

    PubMed Central

    Aslam, Saima; Darouiche, Rabih O.

    2012-01-01

    Prosthetic joint infections represent a major therapeutic challenge for both healthcare providers and patients. This paper reviews the predisposing factors, pathogenesis, microbiology, diagnosis, treatment and prophylaxis of prosthetic joint infection. The most optimal management strategy should be identified based on a number of considerations including type and duration of infection, antimicrobial susceptibility of the infecting pathogen, condition of infected tissues and bone stock, patient wishes and functional status. PMID:22847032

  4. Elbow joint fatigue and bench-press training.

    PubMed

    Huang, Yen-Po; Chou, You-Li; Chen, Feng-Chun; Wang, Rong-Tyai; Huang, Ming-Jer; Chou, Paul Pei-Hsi

    2014-01-01

    Bench-press exercises are among the most common form of training exercise for the upper extremity because they yield a notable improvement in both muscle strength and muscle endurance. The literature contains various investigations into the effects of different bench-press positions on the degree of muscle activation. However, the effects of fatigue on the muscular performance and kinetics of the elbow joint are not understood fully. To investigate the effects of fatigue on the kinetics and myodynamic performance of the elbow joint in bench-press training. Controlled laboratory study. Motion research laboratory. A total of 18 physically healthy male students (age = 19.6 ± 0.8 years, height = 168.7 ± 5.5 cm, mass = 69.6 ± 8.6 kg) participated in the investigation. All participants were right-hand dominant, and none had a history of upper extremity injuries or disorders. Participants performed bench-press training until fatigued. Maximal possible number of repetitions, cycle time, myodynamic decline rate, elbow-joint force, and elbow-joint moment. We observed a difference in cycle time in the initial (2.1 ± 0.42 seconds) and fatigue (2.58 ± 0.46 seconds) stages of the bench-press exercise (P = .04). As the participants fatigued, we observed an increase in the medial-lateral force (P = .03) and internal-external moment (P ≤ .04) acting on the elbow joint. Moreover, a reduction in the elbow muscle strength was observed in the elbow extension-flexion (P ≤ .003) and forearm supination-pronation (P ≤ .001) conditions. The results suggest that performing bench-press exercises to the point of fatigue increases elbow-joint loading and may further increase the risk of injury. Therefore, when clinicians design bench-press exercise regimens for general athletic training, muscle strengthening, or physical rehabilitation, they should control carefully the maximal number of repetitions.

  5. Common Bolted Joint Analysis Tool

    NASA Technical Reports Server (NTRS)

    Imtiaz, Kauser

    2011-01-01

    Common Bolted Joint Analysis Tool (comBAT) is an Excel/VB-based bolted joint analysis/optimization program that lays out a systematic foundation for an inexperienced or seasoned analyst to determine fastener size, material, and assembly torque for a given design. Analysts are able to perform numerous what-if scenarios within minutes to arrive at an optimal solution. The program evaluates input design parameters, performs joint assembly checks, and steps through numerous calculations to arrive at several key margins of safety for each member in a joint. It also checks for joint gapping, provides fatigue calculations, and generates joint diagrams for a visual reference. Optimum fastener size and material, as well as correct torque, can then be provided. Analysis methodology, equations, and guidelines are provided throughout the solution sequence so that this program does not become a "black box:" for the analyst. There are built-in databases that reduce the legwork required by the analyst. Each step is clearly identified and results are provided in number format, as well as color-coded spelled-out words to draw user attention. The three key features of the software are robust technical content, innovative and user friendly I/O, and a large database. The program addresses every aspect of bolted joint analysis and proves to be an instructional tool at the same time. It saves analysis time, has intelligent messaging features, and catches operator errors in real time.

  6. Adhesive-bonded scarf and stepped-lap joints

    NASA Technical Reports Server (NTRS)

    Hart-Smith, L. J.

    1973-01-01

    Continuum mechanics solutions are derived for the static load-carrying capacity of scarf and stepped-lap adhesive-bonded joints. The analyses account for adhesive plasticity and adherend stiffness imbalance and thermal mismatch. The scarf joint solutions include a simple algebraic formula which serves as a close lower bound, within a small fraction of a per cent of the true answer for most practical geometries and materials. Digital computer programs were developed and, for the stepped-lap joints, the critical adherend and adhesive stresses are computed for each step. The scarf joint solutions exhibit grossly different behavior from that for double-lap joints for long overlaps inasmuch as that the potential bond shear strength continues to increase with indefinitely long overlaps on the scarf joints. The stepped-lap joint solutions exhibit some characteristics of both the scarf and double-lap joints. The stepped-lap computer program handles arbitrary (different) step lengths and thickness and the solutions obtained have clarified potentially weak design details and the remedies. The program has been used effectively to optimize the joint proportions.

  7. Synovitis induced by joint lavage with hypertonic saline solutions in healthy dairy calves

    PubMed Central

    Achard, Damien; Francoz, David; Desrochers, André; Girard, Christiane; Piché, Caroline

    2012-01-01

    The objective of this study was to evaluate the effect of a single joint lavage with 7.2% or 15% hypertonic saline solutions (HSS) on the tarsocrural joints of healthy calves. The tarsi of 10 calves were randomly lavaged with 7.2% HSS, 15% HSS, or isotonic saline. Synovial fluid samples were collected aseptically on days 1 (before joint lavage), 2, 3, 4, and 8 for complete cytological analysis. Lameness, joint swelling, and pain were recorded daily. Calves were euthanized on day 8 for gross and histological analyses of synovial membranes and articular cartilage. Synovitis was evaluated using a scoring system reflecting inflammatory changes in synovial membranes. Joints irrigated with HSS were more distended and painful compared with isotonic control joints. Swelling decreased consistently in the joints lavaged with 7.2% HSS, whereas it remained unchanged in joints lavaged with 15% HSS. Slight to moderate lameness was observed in the joints lavaged with 15% HSS. In comparison to isotonic saline joints, total protein concentration was significantly increased on day 2 and 3 for the joints lavaged with 7.2% HSS (P ≤ 0.01) and on days 2, 3, and 4 in the joints lavaged with 15% HSS (P ≤ 0.0006). Gross and histological findings revealed that synovitis was more severe in the joints lavaged with 15% HSS but variable in the joints lavaged with 7.2% HSS. No significant differences were observed for the articular cartilage. Fifteen percent HSS is not recommended for joint lavage. Although irrigation with 7.2% HSS may induce a variable synovitis, it was found appropriate for joint lavage. Its effects on septic joints remain undetermined. PMID:23024450

  8. Family joint activities in a cross-national perspective.

    PubMed

    Zaborskis, Apolinaras; Zemaitiene, Nida; Borup, Ina; Kuntsche, Emmanuel; Moreno, Carmen

    2007-05-30

    Parents and children joint activities are considered to be an important factor on healthy lifestyle development throughout adolescence. This study is a part of the Cross-National Survey on Health Behaviour in School-aged Children--World Health Organization Collaborative Study (HBSC). It aims to describe family time in joint activities and to clarify the role of social and structural family profile in a cross-national perspective. The research was carried out according to the methodology of the HBSC study using the anonymous standardized questionnaire. In total, 17,761 students (8,649 boys and 9,112 girls) aged 13 and 15 years from 6 European countries (Czech Republic, Finland, Greenland, Lithuania, Spain, and Ukraine) were surveyed in the 2001-2002 school-year. The evaluation of joint family activity is based on 8 items: (1) watching TV or a video, (2) playing indoor games, (3) eating meals, (4) going for a walk, (5) going places, (6) visiting friends or relatives, (7) playing sports, (8) sitting and talking about things (chatting). Students from Spain and Ukraine reported spending the most time together with their families in almost all kinds of joint activities, whereas students from Greenland and Finland reported spending the least of this time. Boys were more likely than girls to be spending time together with family. Joint family activity goes into decline in age from 13 to 15 years. Variability of family time in a cross-national perspective was relatively small and related to children age category. Considering national, gender and age differences of studied population groups, we found that the distribution of joint family activities tends to be dispersed significantly by family structure (intact/restructured family) and family wealth. Our study compares children and parent joint activities in European countries and reveals differences and similarities in these patterns between countries. The findings underline the role of family structure (intact

  9. Joint-layer encoder optimization for HEVC scalable extensions

    NASA Astrophysics Data System (ADS)

    Tsai, Chia-Ming; He, Yuwen; Dong, Jie; Ye, Yan; Xiu, Xiaoyu; He, Yong

    2014-09-01

    Scalable video coding provides an efficient solution to support video playback on heterogeneous devices with various channel conditions in heterogeneous networks. SHVC is the latest scalable video coding standard based on the HEVC standard. To improve enhancement layer coding efficiency, inter-layer prediction including texture and motion information generated from the base layer is used for enhancement layer coding. However, the overall performance of the SHVC reference encoder is not fully optimized because rate-distortion optimization (RDO) processes in the base and enhancement layers are independently considered. It is difficult to directly extend the existing joint-layer optimization methods to SHVC due to the complicated coding tree block splitting decisions and in-loop filtering process (e.g., deblocking and sample adaptive offset (SAO) filtering) in HEVC. To solve those problems, a joint-layer optimization method is proposed by adjusting the quantization parameter (QP) to optimally allocate the bit resource between layers. Furthermore, to make more proper resource allocation, the proposed method also considers the viewing probability of base and enhancement layers according to packet loss rate. Based on the viewing probability, a novel joint-layer RD cost function is proposed for joint-layer RDO encoding. The QP values of those coding tree units (CTUs) belonging to lower layers referenced by higher layers are decreased accordingly, and the QP values of those remaining CTUs are increased to keep total bits unchanged. Finally the QP values with minimal joint-layer RD cost are selected to match the viewing probability. The proposed method was applied to the third temporal level (TL-3) pictures in the Random Access configuration. Simulation results demonstrate that the proposed joint-layer optimization method can improve coding performance by 1.3% for these TL-3 pictures compared to the SHVC reference encoder without joint-layer optimization.

  10. Dynamic Analyses Including Joints Of Truss Structures

    NASA Technical Reports Server (NTRS)

    Belvin, W. Keith

    1991-01-01

    Method for mathematically modeling joints to assess influences of joints on dynamic response of truss structures developed in study. Only structures with low-frequency oscillations considered; only Coulomb friction and viscous damping included in analysis. Focus of effort to obtain finite-element mathematical models of joints exhibiting load-vs.-deflection behavior similar to measured load-vs.-deflection behavior of real joints. Experiments performed to determine stiffness and damping nonlinearities typical of joint hardware. Algorithm for computing coefficients of analytical joint models based on test data developed to enable study of linear and nonlinear effects of joints on global structural response. Besides intended application to large space structures, applications in nonaerospace community include ground-based antennas and earthquake-resistant steel-framed buildings.

  11. Joint contact forces can be reduced by improving joint moment symmetry in below-knee amputee gait simulations.

    PubMed

    Koelewijn, Anne D; van den Bogert, Antonie J

    2016-09-01

    Despite having a fully functional knee and hip in both legs, asymmetries in joint moments of the knee and hip are often seen in gait of persons with a unilateral transtibial amputation (TTA), possibly resulting in excessive joint loading. We hypothesize that persons with a TTA can walk with more symmetric joint moments at the cost of increased effort or abnormal kinematics. The hypothesis was tested using predictive simulations of gait. Open loop controls of one gait cycle were found by solving an optimization problem that minimizes a combination of walking effort and tracking error in joint angles, ground reaction force and gait cycle duration. A second objective was added to penalize joint moment asymmetry, creating a multi-objective optimization problem. A Pareto front was constructed by changing the weights of the objectives and three solutions were analyzed to study the effect of increasing joint moment symmetry. When the optimization placed more weight on moment symmetry, walking effort increased and kinematics became less normal, confirming the hypothesis. TTA gait improved with a moderate increase in joint moment symmetry. At a small cost of effort and abnormal kinematics, the peak hip extension moment in the intact leg was decreased significantly, and so was the joint contact force in the knee and hip. Additional symmetry required a significant increase in walking effort and the joint contact forces in both hips became significantly higher than in able-bodied gait. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. 77 FR 39560 - International Joint Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-03

    ... DEPARTMENT OF STATE [Public Notice 7945] International Joint Commission International Joint Commission Invites Public Comment on Upper Great Lakes Report The International Joint Commission (IJC) announced today that it is inviting public comment on the final report of its International Upper Great...

  13. Joint torques in a freely walking insect reveal distinct functions of leg joints in propulsion and posture control

    PubMed Central

    2016-01-01

    Determining the mechanical output of limb joints is critical for understanding the control of complex motor behaviours such as walking. In the case of insect walking, the neural infrastructure for single-joint control is well described. However, a detailed description of the motor output in form of time-varying joint torques is lacking. Here, we determine joint torques in the stick insect to identify leg joint function in the control of body height and propulsion. Torques were determined by measuring whole-body kinematics and ground reaction forces in freely walking animals. We demonstrate that despite strong differences in morphology and posture, stick insects show a functional division of joints similar to other insect model systems. Propulsion was generated by strong depression torques about the coxa–trochanter joint, not by retraction or flexion/extension torques. Torques about the respective thorax–coxa and femur–tibia joints were often directed opposite to fore–aft forces and joint movements. This suggests a posture-dependent mechanism that counteracts collapse of the leg under body load and directs the resultant force vector such that strong depression torques can control both body height and propulsion. Our findings parallel propulsive mechanisms described in other walking, jumping and flying insects, and challenge current control models of insect walking. PMID:26791608

  14. Position of the prosthesis components in total ankle replacement and the effect on motion at the replaced joint.

    PubMed

    Cenni, Francesco; Leardini, Alberto; Cheli, Andrea; Catani, Fabio; Belvedere, Claudio; Romagnoli, Matteo; Giannini, Sandro

    2012-03-01

    In some cases of total ankle replacement, perfect alignment of the prosthetic components is not achieved. This study analyses the extent to which component positioning is critical for the final range of motion. Fourteen patients undergoing total ankle replacement were assessed preoperatively and postoperatively at seven and 13 months follow-up. X-ray pictures of the ankle were taken in static double leg stance, i.e. at neutral joint position, and in maximum plantarflexion and dorsiflexion. Measurements were obtained by a specially devised computer program based on anatomical reference points digitised on the radiograms. These allowed calculation of the position and orientation of the components in the sagittal and coronal planes, together with the joint range of motion. The mean range of motion was about 34 degrees at the first follow-up and maintained at the second. Tibial and talar components were more anterior than the mid-tibial shaft in 11 and nine patients, respectively. Mean inclination was about four degrees posterior for the tibial component and nearly one degree anterior for the talar component. A significantly larger range of motion was found in ankles both with the talar component located and inclined more anteriorly than the tibial. Correlation, though weak, was found between motion at the replaced ankle and possible residual subluxation and inclination of the components. However, a satisfactory range of motion was also achieved in those patients where recommended locations for the components could not be reached because of the size of the original joint deformity.

  15. Early Osteoarthritis of the Trapeziometacarpal Joint Is Not Associated With Joint Instability during Typical Isometric Loading

    PubMed Central

    Halilaj, Eni; Moore, Douglas C.; Patel, Tarpit K.; Ladd, Amy L.; Weiss, Arnold-Peter C.; Crisco, Joseph J.

    2015-01-01

    The saddle-shaped trapeziometacarpal (TMC) joint contributes importantly to the function of the human thumb. A balance between mobility and stability is essential in this joint, which experiences high loads and is prone to osteoarthritis (OA). Since instability is considered a risk factor for TMC OA, we assessed TMC joint instability during the execution of three isometric functional tasks (key pinch, jar grasp, and jar twist) in 76 patients with early TMC OA and 44 asymptomatic controls. Computed tomography images were acquired while subjects held their hands relaxed and while they applied 80% of their maximum effort for each task. Six degree-of-freedom rigid body kinematics of the metacarpal with respect to the trapezium from the unloaded to the loaded task positions were computed in terms of a TMC joint coordinate system. Joint instability was expressed as a function of the metacarpal translation and the applied force. We found that the TMC joint was more unstable during a key pinch task than during a jar grasp or a jar twist task. Sex, age, and early OA did not have an effect on TMC joint instability, suggesting that instability during these three tasks is not a predisposing factor in TMC OA. PMID:25941135

  16. Improved Automatically Locking/Unlocking Orthotic Knee Joint

    NASA Technical Reports Server (NTRS)

    Weddendorf, Bruce

    1995-01-01

    Proposed orthotic knee joint improved version of one described in "Automatically Locking/Unlocking Orthotic Knee Joint" (MFS-28633). Locks automatically upon initial application of radial force (wearer's weight) and unlocks automatically, but only when all loads (radial force and bending) relieved. Joints lock whenever wearer applies weight to knee at any joint angle between full extension and 45 degree bend. Both devices offer increased safety and convenience relative to conventional orthotic knee joints.

  17. Resource utilization and costs before and after total joint arthroplasty.

    PubMed

    Bozic, Kevin J; Stacey, Brett; Berger, Ariel; Sadosky, Alesia; Oster, Gerry

    2012-03-23

    The purpose of this study was to compare pre- and post-surgical healthcare costs in commercially insured total joint arthroplasty (TJA) patients with osteoarthritis (OA) in the United States (U.S.). Using a large healthcare claims database, we identified patients over age 39 with hip or knee OA who underwent unilateral primary TJA (hip or knee) between 1/1/2006 and 9/30/2007. Utilization of healthcare services and costs were aggregated into three periods: 12 months "pre-surgery," 91 days "peri-operative," and 3 to 15 month "follow-up," Mean total pre-surgery costs were compared with follow-up costs using Wilcoxon signed-rank test. 14,912 patients met inclusion criteria for the study. The mean total number of outpatient visits declined from pre-surgery to follow-up (18.0 visits vs 17.1), while the percentage of patients hospitalized increased (from 7.5% to 9.8%) (both p < 0.01). Mean total costs during the follow-up period were 18% higher than during pre-surgery ($11,043 vs. $9,632, p < 0.01), largely due to an increase in the costs of inpatient care associated with hospital readmissions ($3,300 vs. $1,817, p < 0.01). Pharmacotherapy costs were similar for both periods ($2013 [follow-up] vs. $1922 [pre-surgery], p = 0.33); outpatient care costs were slightly lower in the follow-up period ($4338 vs. $4571, p < 0.01). Mean total costs for the peri-operative period were $36,553. Mean total utilization of outpatient healthcare services declined slightly in the first year following TJA (exclusive of the peri-operative period), while mean total healthcare costs increased during the same time period, largely due to increased costs associated with hospital readmissions. Further study is necessary to determine whether healthcare costs decrease in subsequent years.

  18. Characteristics of Hemorrhagic Stroke following Spine and Joint Surgeries.

    PubMed

    Yang, Fei; Zhao, Jianning; Xu, Haidong

    2017-01-01

    Hemorrhagic stroke can occur after spine and joint surgeries such as laminectomy, lumbar spinal fusion, tumor resection, and total joint arthroplasty. Although this kind of stroke rarely happens, it may cause severe consequences and high mortality rates. Typical clinical symptoms of hemorrhagic stroke after spine and joint surgeries include headache, vomiting, consciousness disturbance, and mental disorders. It can happen several hours after surgeries. Most bleeding sites are located in cerebellar hemisphere and temporal lobe. A cerebrospinal fluid (CSF) leakage caused by surgeries may be the key to intracranial hemorrhages happening. Early diagnosis and treatments are very important for patients to prevent the further progression of intracranial hemorrhages. Several patients need a hematoma evacuation and their prognosis is not optimistic.

  19. Management of lumbar zygapophysial (facet) joint pain

    PubMed Central

    Manchikanti, Laxmaiah; Hirsch, Joshua A; Falco, Frank JE; Boswell, Mark V

    2016-01-01

    . RESULTS: Across all databases, 16 high quality diagnostic accuracy studies were identified. In addition, multiple studies assessed the influence of multiple factors on diagnostic validity. In contrast to diagnostic validity studies, therapeutic efficacy trials were limited to a total of 14 randomized controlled trials, assessing the efficacy of intraarticular injections, facet or zygapophysial joint nerve blocks, and radiofrequency neurotomy of the innervation of the facet joints. The evidence for the diagnostic validity of lumbar facet joint nerve blocks with at least 75% pain relief with ability to perform previously painful movements was level I, based on a range of level I to V derived from a best evidence synthesis. For therapeutic interventions, the evidence was variable from level II to III, with level II evidence for lumbar facet joint nerve blocks and radiofrequency neurotomy for long-term improvement (greater than 6 mo), and level III evidence for lumbosacral zygapophysial joint injections for short-term improvement only. CONCLUSION: This review provides significant evidence for the diagnostic validity of facet joint nerve blocks, and moderate evidence for therapeutic radiofrequency neurotomy and therapeutic facet joint nerve blocks in managing chronic low back pain. PMID:27190760

  20. Real-Time Visualization of Joint Cavitation

    PubMed Central

    Rowe, Lindsay

    2015-01-01

    Cracking sounds emitted from human synovial joints have been attributed historically to the sudden collapse of a cavitation bubble formed as articular surfaces are separated. Unfortunately, bubble collapse as the source of joint cracking is inconsistent with many physical phenomena that define the joint cracking phenomenon. Here we present direct evidence from real-time magnetic resonance imaging that the mechanism of joint cracking is related to cavity formation rather than bubble collapse. In this study, ten metacarpophalangeal joints were studied by inserting the finger of interest into a flexible tube tightened around a length of cable used to provide long-axis traction. Before and after traction, static 3D T1-weighted magnetic resonance images were acquired. During traction, rapid cine magnetic resonance images were obtained from the joint midline at a rate of 3.2 frames per second until the cracking event occurred. As traction forces increased, real-time cine magnetic resonance imaging demonstrated rapid cavity inception at the time of joint separation and sound production after which the resulting cavity remained visible. Our results offer direct experimental evidence that joint cracking is associated with cavity inception rather than collapse of a pre-existing bubble. These observations are consistent with tribonucleation, a known process where opposing surfaces resist separation until a critical point where they then separate rapidly creating sustained gas cavities. Observed previously in vitro, this is the first in-vivo macroscopic demonstration of tribonucleation and as such, provides a new theoretical framework to investigate health outcomes associated with joint cracking. PMID:25875374

  1. Facet joint disturbance induced by miniscrews in plated cervical laminoplasty

    PubMed Central

    Chen, Hua; Li, Huibo; Wang, Beiyu; Li, Tao; Gong, Quan; Song, Yueming; Liu, Hao

    2016-01-01

    Abstract A retrospective cohort study. Plated cervical laminoplasty is an increasingly common technique. A unique facet joint disturbance induced by lateral mass miniscrews penetrating articular surface was noticed. Facet joints are important to maintain cervical spine stability and kinetic balance. Whether this facet joint disturbance could affect clinical and radiologic results is still unknown. The objective of this study is to investigate the clinical and radiologic outcomes of patients with facet joints disturbance induced by miniscrews in plated cervical laminoplasty. A total of 105 patients who underwent cervical laminoplasty with miniplate fixation between May 2010 and February 2014 were comprised. Postoperative CT images were used to identify whether facet joints destroyed by miniscrews. According to facet joints destroyed number, all the patients were divided into: group A (none facet joint destroyed), group B (1–2 facet joints destroyed), and group C (≥3 facet joints destroyed). Clinical data (JOA, VAS, and NDI scores), radiologic data (anteroposterior diameter and Palov ratio), and complications (axial symptoms and C5 palsy) were evaluated and compared among the groups. There were 38, 40, and 27 patients in group A, B, and C, respectively. The overall facet joints destroyed rate was 30.7%. All groups gained significant JOA and NDI scores improvement postoperatively. The preoperative JOA, VAS, NDI scores, and postoperative JOA scores did not differ significantly among the groups. The group C recorded significant higher postoperative VAS scores than group A (P = 0.002) and B (P = 0.014) and had significant higher postoperative NDI scores than group A (P = 0.002). The pre- and postoperative radiologic data were not significant different among the groups. The group C had a significant higher axial symptoms incidence than group A (12/27 vs 8/38, P = 0.041). Facet joints disturbance caused by miniscrews in plated cervical laminoplasty may not influence

  2. 15 CFR 296.8 - Joint venture agreement.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... OF STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE NIST EXTRAMURAL PROGRAMS TECHNOLOGY INNOVATION PROGRAM General § 296.8 Joint venture agreement. NIST shall not issue a TIP award to a joint venture and... joint venture agreement has been executed by all of the joint venture members and approved by NIST. ...

  3. 15 CFR 296.8 - Joint venture agreement.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... OF STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE NIST EXTRAMURAL PROGRAMS TECHNOLOGY INNOVATION PROGRAM General § 296.8 Joint venture agreement. NIST shall not issue a TIP award to a joint venture and... joint venture agreement has been executed by all of the joint venture members and approved by NIST. ...

  4. 15 CFR 296.8 - Joint venture agreement.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... OF STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE NIST EXTRAMURAL PROGRAMS TECHNOLOGY INNOVATION PROGRAM General § 296.8 Joint venture agreement. NIST shall not issue a TIP award to a joint venture and... joint venture agreement has been executed by all of the joint venture members and approved by NIST. ...

  5. 15 CFR 296.8 - Joint venture agreement.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... OF STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE NIST EXTRAMURAL PROGRAMS TECHNOLOGY INNOVATION PROGRAM General § 296.8 Joint venture agreement. NIST shall not issue a TIP award to a joint venture and... joint venture agreement has been executed by all of the joint venture members and approved by NIST. ...

  6. 15 CFR 296.8 - Joint venture agreement.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... OF STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE NIST EXTRAMURAL PROGRAMS TECHNOLOGY INNOVATION PROGRAM General § 296.8 Joint venture agreement. NIST shall not issue a TIP award to a joint venture and... joint venture agreement has been executed by all of the joint venture members and approved by NIST. ...

  7. Structural analysis of Aircraft fuselage splice joint

    NASA Astrophysics Data System (ADS)

    Udaya Prakash, R.; Kumar, G. Raj; Vijayanandh, R.; Senthil Kumar, M.; Ramganesh, T.

    2016-09-01

    In Aviation sector, composite materials and its application to each component are one of the prime factors of consideration due to the high strength to weight ratio, design flexibility and non-corrosive so that the composite materials are widely used in the low weight constructions and also it can be treated as a suitable alternative to metals. The objective of this paper is to estimate and compare the suitability of a composite skin joint in an aircraft fuselage with different joints by simulating the displacement, normal stress, vonmises stress and shear stress with the help of numerical solution methods. The reference Z-stringer component of this paper is modeled by CATIA and numerical simulation is carried out by ANSYS has been used for splice joint presents in the aircraft fuselage with three combinations of joints such as riveted joint, bonded joint and hybrid joint. Nowadays the stringers are using to avoid buckling of fuselage skin, it has joined together by rivets and they are connected end to end by splice joint. Design and static analysis of three-dimensional models of joints such as bonded, riveted and hybrid are carried out and results are compared.

  8. Dorsoradial capsulodesis for trapeziometacarpal joint instability.

    PubMed

    Rayan, Ghazi; Do, Viet

    2013-02-01

    We describe an alternative method for treating chronic trapeziometacarpal (TM) joint instability after acute injury or chronic repetitive use of the thumb by performing a dorsoradial capsulodesis procedure. The procedure is done by imbricating the redundant TM joint dorsoradial ligament and capsule after reducing the joint by pronating the thumb. The dorsoradial capsulodesis is a reasonable reconstructive option for chronic TM joint instability and subluxation. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  9. Fluoroscopic Sacroiliac Joint Injection: Is Oblique Angulation Really Necessary?

    PubMed

    Khuba, Sandeep; Agarwal, Anil; Gautam, Sujeet; Kumar, Sanjay

    2016-01-01

    The conventional technique for sacroiliac (SI) joint injection involves aligning the anterior and posterior aspects of the SI joint under fluoroscopic guidance and then entering the SI joint in the most caudal aspect. We wish to highlight that there is no added advantage to aligning both the anterior and posterior joint lines of the SI joint as it is time consuming, associated with additional radiation exposure, and may make the entry into the posterior SI joint technically more difficult. Observational study. Pain Clinic, Department of Anesthesiology. With the patient lying prone on fluoroscopy table, SI joint injection is performed with a 22 G, 10 cm spinal needle in a true anteroposterior (AP) view, where anterior and posterior SI joint spaces are seen as separate entities, where the medial joint space represents the posterior SI joint and the lateral joint space represents the anterior SI joint. The distal 1 cm of the medial joint space is entered under AP view. If the SI joint is seen as a straight line rather than 2 joint spaces in the AP view then the image intensifier of the fluoroscope was tilted cranially to elongate the image of the lower part of the posterior SI joint, thus facilitating entry into this part of the joint which was confirmed by administering 0.3 to 0.5 mL of radiopaque contrast medium. Sixty SI joints of 58 patients were injected under an AP fluoroscopic view. Forty-two (70%) SI joints were seen as 2 separate medial and lateral joint spaces and were entered in distal 1 cm of the medial joint space. In 18 (30%) joints seen as a straight line rather than 2 separate spaces, the image intensifier of the fluoroscope was tilted cranially to elongate the image of the lower part of the posterior SI joint and then the SI joint was entered in its distal 1 cm. Confirmation of entry into the SI joint was confirmed by with 0.3 to 0.5 mL of radiopaque contrast medium. In 4 cases the joints did not show the correct radiopaque contrast spread (3/42 and 1

  10. A comparison of manual and electronic counting for total nucleated cell counts on synovial fluid from canine stifle joints.

    PubMed

    Atilola, M A; Lumsden, J H; Rooke, F

    1986-04-01

    Synovial fluids collected from the stifle joints of 20 physically normal adult dogs were subjected to cytological examination. A total nucleated cell count was performed on each sample using both an electronic cell counter and a hemocytometer. The mean of the total counts done with the electronic counter was significantly higher (1008 cells/microL) than that obtained manually with the hemocytometer (848 cells/microL).

  11. Effects of load proportioning on the capacity of multiple-hole composite joints

    NASA Technical Reports Server (NTRS)

    Hyer, M. W.; Chastain, P. A.

    1985-01-01

    This study addresses the issue of adjusting the proportion of load transmitted by each hole in a multiple-hole joint so that the joint capacity is a maximum. Specifically two-hole-in-series joints are examined. The results indicate that when each hole reacts 50% of the total load, the joint capacity is not a maximum. One hole generally is understressed at joint failure. The algorithm developed to determine the load proportion at each hole which results in maximum capacity is discussed. The algorithm includes two-dimensional finite-element stress analysis and failure criteria. The algorithm is used to study the effects of joint width, hole spacing, and hole to joint-end distance on load proportioning and capacity. To study hole size effects, two hole diameters are considered. Three laminates are considered: a quasi-isotropic laminate; a cross-ply laminate; and a 45 degree angle-ply laminate. By proportioning the load, capacity can be increased generally from 5 to 10%. In some cases a greater increase is possible.

  12. Associations between socioeconomic status and primary total knee joint replacements performed for osteoarthritis across Australia 2003-10: data from the Australian Orthopaedic Association National Joint Replacement Registry.

    PubMed

    Brennan, Sharon L; Lane, Stephen E; Lorimer, Michelle; Buchbinder, Rachelle; Wluka, Anita E; Page, Richard S; Osborne, Richard H; Pasco, Julie A; Sanders, Kerrie M; Cashman, Kara; Ebeling, Peter R; Graves, Stephen E

    2014-10-28

    Relatively little is known about the social distribution of total knee joint replacement (TKR) uptake in Australia. We examine associations between socioeconomic status (SES) and TKR performed for diagnosed osteoarthritis 2003-10 for all Australian males and females aged ≥ 30 yr. Data of primary TKR (n=213,018, 57.4% female) were ascertained from a comprehensive national joint replacement registry. Residential addresses were matched to Australian Census data to identify area-level social disadvantage, and categorised into deciles. Estimated TKR rates were calculated. Poisson regression was used to model the relative risk (RR) of age-adjusted TKR per 1,000py, stratified by sex and SES. A negative relationship was observed between TKR rates and SES deciles. Females had a greater rate of TKR than males. Surgery utilisation was greatest for all adults aged 70-79 yr. In that age group differences in estimated TKR per 1,000py between deciles were greater for 2010 than 2003 (females: 2010 RR 4.32 and 2003 RR 3.67; males: 2010 RR 2.04 and 2003 RR 1.78). Identifying factors associated with TKR utilisation and SES may enhance resource planning and promote surgery utilisation for end-stage osteoarthritis.

  13. Increased expression of damage-associated molecular patterns (DAMPs) in osteoarthritis of human knee joint compared to hip joint.

    PubMed

    Rosenberg, John H; Rai, Vikrant; Dilisio, Matthew F; Sekundiak, Todd D; Agrawal, Devendra K

    2017-12-01

    Osteoarthritis (OA) is a degenerative disease characterized by the destruction of cartilage. The greatest risk factors for the development of OA include age and obesity. Recent studies suggest the role of inflammation in the pathogenesis of OA. The two most common locations for OA to occur are in the knee and hip joints. The knee joint experiences more mechanical stress, cartilage degeneration, and inflammation than the hip joint. This could contribute to the increased incidence of OA in the knee joint. Damage-associated molecular patterns (DAMPs), including high-mobility group box-1, receptor for advanced glycation end products, and alarmins (S100A8 and S100A9), are released in the joint in response to stress-mediated chondrocyte and cartilage damage. This facilitates increased cartilage degradation and inflammation in the joint. Studies have documented the role of DAMPs in the pathogenesis of OA; however, the comparison of DAMPs and its influence on OA has not been discussed. In this study, we compared the DAMPs between OA knee and hip joints and found a significant difference in the levels of DAMPs expressed in the knee joint compared to the hip joint. The increased levels of DAMPs suggest a difference in the underlying pathogenesis of OA in the knee and the hip and highlights DAMPs as potential therapeutic targets for OA in the future.

  14. 49 CFR 213.351 - Rail joints.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... replaced. (d) Each rail shall be bolted with at least two bolts at each joint. (e) Each joint bar shall be... in this subpart. (f) No rail shall have a bolt hole which is torch cut or burned. (g) No joint bar shall be reconfigured by torch cutting. ...

  15. Objective Assessment of Joint Stiffness: A Clinically Oriented Hardware and Software Device with an Application to the Shoulder Joint.

    PubMed

    McQuade, Kevin; Price, Robert; Liu, Nelson; Ciol, Marcia A

    2012-08-30

    Examination of articular joints is largely based on subjective assessment of the "end-feel" of the joint in response to manually applied forces at different joint orientations. This technical report aims to describe the development of an objective method to examine joints in general, with specific application to the shoulder, and suitable for clinical use. We adapted existing hardware and developed laptop-based software to objectively record the force/displacement behavior of the glenohumeral joint during three common manual joint examination tests with the arm in six positions. An electromagnetic tracking system recorded three-dimensional positions of sensors attached to a clinician examiner and a patient. A hand-held force transducer recorded manually applied translational forces. The force and joint displacement were time-synchronized and the joint stiffness was calculated as a quantitative representation of the joint "end-feel." A methodology and specific system checks were developed to enhance clinical testing reproducibility and precision. The device and testing protocol were tested on 31 subjects (15 with healthy shoulders, and 16 with a variety of shoulder impairments). Results describe the stiffness responses, and demonstrate the feasibility of using the device and methods in clinical settings.

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

    PubMed

    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

  17. Joint Newspaper Operating Agreements.

    ERIC Educational Resources Information Center

    Parsons, Marie

    The number of competing daily newspapers in American cities has dwindled until only about 50 cities boast two papers. Of the newspapers in those cities, 23 now maintain separate editorial operations but have joint printing, advertising, and circulation departments. The concept of joint operation is 50 years old, dating from the Depression years…

  18. Survivorship of Total Hip Joint Replacements Following Isolated Liner Exchange for Wear.

    PubMed

    Vadei, Leone; Kieser, David C; Frampton, Chris; Hooper, Gary

    2017-11-01

    Liner exchange for articular component wear in total hip joint replacements (THJRs) is a common procedure, often thought to be benign with reliable outcomes. Recent studies, however, suggest high failure rates of liner exchange revisions with significant complications. The primary aim of this study was, therefore, to analyze the survivorship of isolated liner exchange for articular component wear, and secondarily to assess the influence of patient demographics (gender, age, and American Society of Anaesthesiologists [ASA] ratings) on rerevisions following isolated liner exchange for wear. A retrospective review of the 15-year New Zealand Joint Registry (1999-2014) was performed, analyzing the outcomes of isolated liner exchange for articular component wear. The survivorship as defined as rerevision with component exchange was determined and 10-year Kaplan-Meier survivorship curves were constructed. These revision rates were compared to age, gender, and ASA rating groups using a log-rank test. The 10-year survivorship of THJR following liner exchange revision for liner wear was 75.3%. If a rerevision was required, the median time to rerevision was 1.33 years with a rerevision rate of 3.33 per 100 component years (95% confidence interval 2.68-4.08/100 component years). The principle reasons for rerevision were dislocation (48.4%) and acetabular component loosening (20.9%). There was no statistically significant difference in rerevision rates based on gender, age categories, or ASA scores. THJR isolated liner exchange for liner wear is not a benign procedure with a survivorship of 75.3% at 10 years. Surgeons contemplating liner exchange revisions should be cognisant of this risk and should adequately assess component position and stability preoperatively. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Strength evaluation of socket joints

    NASA Technical Reports Server (NTRS)

    Rash, Larry C.

    1994-01-01

    This report documents the development of a set of equations that can be used to provide a relatively simple solution for identifying the strength of socket joints and for most cases avoid the need of more lengthy analyses. The analytical approach was verified by comparison of the contact load distributions to results obtained from a finite element analysis. The contacting surfaces for the specific joint in this analysis are in the shape of frustrums of a cone and are representative of the tapered surfaces in the socket-type joints used to join segments of model support systems for wind tunnels. The results are in the form of equations that can be used to determine the contact loads and stresses in the joint from the given geometry and externally applied loads. Equations were determined to define the bending moments and stresses along the length of the joints based on strength and materials principles. The results have also been programmed for a personal computer and a copy of the program is included.

  20. 37 CFR 1.45 - Joint inventors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... joint application under 35 U.S.C. 116. If multiple inventors are named in a provisional application... disclosed in the provisional application and the provisional application will be considered to be a joint... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Joint inventors. 1.45 Section...

  1. BIOMECHANICS AND PATHOMECHANICS OF THE PATELLOFEMORAL JOINT

    PubMed Central

    2016-01-01

    The patellofemoral joint is a joint that can be an area of concern for athletes of various sports and ages. The joint is somewhat complex with multiple contact points and numerous tissues that attach to the patella. Joint forces are variable and depend on the degree of knee flexion and whether the foot is in contact with the ground. The sports medicine specialist must have a good working knowledge of the anatomy and biomechanics of the patellofemoral joint in order to treat it effectively. PMID:27904787

  2. Neuromuscular prehabilitation to prevent osteoarthritis after a traumatic joint injury.

    PubMed

    Tenforde, Adam S; Shull, Pete B; Fredericson, Michael

    2012-05-01

    Post-traumatic osteoarthritis (PTOA) is a process resulting from direct forces applied to a joint that cause injury and degenerative changes. An estimated 12% of all symptomatic osteoarthritis (OA) of the hip, knee, and ankle can be attributed to a post-traumatic cause. Neuromuscular prehabilitation is the process of improving neuromuscular function to prevent development of PTOA after an initial traumatic joint injury. Prehabilitation strategies include restoration of normative movement patterns that have been altered as the result of traumatic injury, along with neuromuscular exercises and gait retraining to prevent the development of OA after an injury occurs. A review of the current literature shows that no studies have been performed to evaluate methods of neuromuscular prehabilitation to prevent PTOA after a joint injury. Instead, current research has focused on management strategies after knee injuries, the value of exercise in the management of OA, and neuromuscular exercises after total knee arthroplasty. Recent work in gait retraining that alters knee joint loading holds promise for preventing the development of PTOA after joint trauma. Future research should evaluate methods of neuromuscular prehabilitation strategies in relationship to the outcome of PTOA after joint injury. Copyright © 2012 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  3. Appropriateness for Total Joint Replacement: Perspectives of Decision-Makers

    PubMed Central

    Clavel, Nathalie; De coster, Carolyn; Pomey, Marie-Pascale; Sanmartin, Claudia; Bohm, Éric; Dunbar, Michael J.; Frank, CY; Hawker, Gillian; Noseworthy, Tom

    2016-01-01

    Background: Improving access to total joint replacement (TJR) has been a priority. Without robust mechanisms to ensure appropriateness, these procedures may be overused, incurring substantial costs. In that context, decision-makers are particularly concerned with the appropriateness of TJR. Objective: While our previous research focused on the appropriateness of TJR from clinical and patient perspectives, this study is aimed at understanding decision-makers' perspectives. Methods: Using a semi-structured guide, we interviewed a convenience sample of decision-makers in four Canadian provinces (Alberta, Manitoba, Nova Scotia and Quebec) between February and March 2013. For the purposes of this study, a decision-maker was defined as a manager, institutional leader or policy maker. Results: Fifteen interviews were conducted with decision-makers at ministry (n = 3), regional (n = 6) and institutional levels (n = 8). Decision-makers see themselves as having a key role in the appropriateness discourse, that of optimizing resource allocation and efficient delivery of services for TJR, to improve population outcomes. Conclusion: The decision-makers' view of appropriateness recognizes the importance of the clinical view, but it offers a very different input into the appropriateness discourse, more closely aligned with appropriateness of setting, which refers to cost-effectiveness considerations. PMID:27027795

  4. Geared Electromechanical Rotary Joint

    NASA Technical Reports Server (NTRS)

    Vranish, John M.

    1994-01-01

    Geared rotary joint provides low-noise ac or dc electrical contact between electrical subsystems rotating relative to each other. Designed to overcome some disadvantages of older electromechanical interfaces, especially intermittency of sliding-contact and rolling-contact electromechanical joints. Hollow, springy planetary gears provide continuous, redundant, low-noise electrical contact between inner and outer gears.

  5. Joint reconstruction of multiview compressed images.

    PubMed

    Thirumalai, Vijayaraghavan; Frossard, Pascal

    2013-05-01

    Distributed representation of correlated multiview images is an important problem that arises in vision sensor networks. This paper concentrates on the joint reconstruction problem where the distributively compressed images are decoded together in order to take benefit from the image correlation. We consider a scenario where the images captured at different viewpoints are encoded independently using common coding solutions (e.g., JPEG) with a balanced rate distribution among different cameras. A central decoder first estimates the inter-view image correlation from the independently compressed data. The joint reconstruction is then cast as a constrained convex optimization problem that reconstructs total-variation (TV) smooth images, which comply with the estimated correlation model. At the same time, we add constraints that force the reconstructed images to be as close as possible to their compressed versions. We show through experiments that the proposed joint reconstruction scheme outperforms independent reconstruction in terms of image quality, for a given target bit rate. In addition, the decoding performance of our algorithm compares advantageously to state-of-the-art distributed coding schemes based on motion learning and on the DISCOVER algorithm.

  6. Functional outcome from sacroiliac joint prolotherapy in patients with sacroiliac joint instability.

    PubMed

    Hoffman, Martin D; Agnish, Vikram

    2018-04-01

    Examine the effectiveness of sacroiliac (SI) joint prolotherapy for SI joint instability, and characterize the patients most likely to benefit from this treatment. Retrospective cohort study. Department of Veterans Affairs outpatient physical medicine clinic. Patients referred for low back pain and diagnosed with SI joint instability received a series of three SI joint prolotherapy injections (15% dextrose in lidocaine) at approximately a one-month interval. The outcome of those completing treatment was retrospectively examined, and characteristics were compared between those with at least a minimum clinically important improvement and those without improvement. Patients completed the Oswestry Disability Index (ODI) before treatment was initiated, immediately preceding each prolotherapy injection, and at 3-4 month follow-up. Of 103 treated patients returning for post-treatment follow-up at a median of 117 days, 24 (23%) showed a minimum clinically important improvement despite a median of 2 years with low back pain and a mean (±SD) pre-intervention ODI of 54 ± 15 points. Much of the improvement was evident after the initial prolotherapy injection, and a 15-point improvement in ODI prior to the second prolotherapy injection had a sensitivity of 92% and specificity of 80% for determining which patients would improve. A satisfactory proportion of patients with symptomatic SI joint instability as an etiology of low back pain can have clinically meaningful functional gains with prolotherapy treatment. The patients who are not likely to improve with prolotherapy are generally evident by lack of improvement following the initial prolotherapy injection. Published by Elsevier Ltd.

  7. Comparison of the use of a notched wedge joint vs. traditional butt joints in Connecticut : phase 1 report.

    DOT National Transportation Integrated Search

    2008-05-14

    Performance of Hot Mix Asphalt (HMA) longitudinal joints have been an : item of increasing scrutiny in Connecticut. The traditional butt joint : has typically been the method used in Connecticut. These joints have : been reportedly opening up creatin...

  8. Outcome of Joint-Preserving Arthroplasty for Rheumatoid Forefoot Deformities.

    PubMed

    Fukushi, Jun-ichi; Nakashima, Yasuharu; Okazaki, Ken; Yamada, Hisakata; Mawatari, Taro; Ohishi, Masanobu; Oyamada, Akiko; Akasaki, Yukio; Iwamoto, Yukihide

    2016-03-01

    Along with the recent advances in the pharmacological management of rheumatoid arthritis, there is a trend toward the use of joint-preserving surgery in the treatment of rheumatoid forefoot deformities. However, the clinical outcomes of joint-preserving surgery for rheumatoid forefoot deformities have not been assessed in comparison to resection arthroplasty. We retrospectively evaluated 23 feet in 17 patients with rheumatoid forefoot deformities who underwent surgery between January 2010 and December 2013. The patients included 1 male (1 foot) and 16 females (22 feet), with a mean age of 62 years. The mean length of follow-up was 28 months. The patients were treated by 3 surgeons. One surgeon performed joint-preserving procedures (JP group) to the feet in which (1) no pain with motion existed, and (2) the range of motion in the first metatarsophalangeal (MTP) joint was greater than 30 degrees (n = 10); otherwise, resection arthroplasty with arthrodesis of the first MTP joint was performed (n = 3). The other surgeons performed resection arthroplasty in all cases (n = 10) (RA group, n = 13 in total). The clinical outcomes of the patients were evaluated using the Japanese Society for Surgery of the Foot (JSSF) hallux and lesser toe scales. There were no significant differences in the preoperative total JSSF scores for either the hallux (54.5 and 61.4 points) or the lesser toe (45.2 and 57.4 points) between the RA and JP groups, respectively. Postoperatively, the total JSSF scores for both the hallux (79.4 and 88.2 points) and lesser toes (73.6 and 87.7 points) showed significant improvement in both the RA and JP groups, respectively; however, the JP group showed a greater postoperative improvement. The scores relating to the function category on the hallux scale and the alignment category on the lesser toe scale were significantly higher in the JP group. With regard to the function of the hallux and the alignment of the lesser toes, the joint-preserving procedures

  9. Blood management and transfusion strategies in 600 patients undergoing total joint arthroplasty: an analysis of pre-operative autologous blood donation.

    PubMed

    Perazzo, Paolo; Viganò, Marco; De Girolamo, Laura; Verde, Francesco; Vinci, Anna; Banfi, Giuseppe; Romagnoli, Sergio

    2013-07-01

    Blood loss during total joint arthroplasty strongly influences the time to recover after surgery and the quality of the recovery. Blood conservation strategies such as pre-operative autologous blood donation and post-operative cell salvage are intended to avoid allogeneic blood transfusions and their associated risks. Although widely investigated, the real effectiveness of these alternative transfusion practices remains controversial. The surgery reports of 600 patients undergoing total joint arthroplasty (312 hip and 288 knee replacements) were retrospectively reviewed to assess transfusion needs and related blood management at our institute. Evaluation parameters included post-operative blood loss, haemoglobin concentration measured at different time points, ASA score, and blood transfusion strategies. Autologous blood donation increased the odds of receiving a red blood cell transfusion. Reinfusion by a cell salvage system of post-operative shed blood was found to limit adverse effects in cases of severe post-operative blood loss. The peri-operative net decrease in haemoglobin concentration was higher in patients who had predeposited autologous blood than in those who had not. The strengths of this study are the high number of cases and the standardised procedures, all operations having been performed by a single orthopaedic surgeon and a single anaesthesiologist. Our data suggest that a pre-operative autologous donation programme may often be useless, if not harmful. Conversely, the use of a cell salvage system may be effective in reducing the impact of blood transfusion on a patient's physiological status. Basal haemoglobin concentration emerged as a useful indicator of transfusion probability in total joint replacement procedures.

  10. Do Changes in Patellofemoral Joint Offset Lead to Adverse Outcomes in Total Knee Arthroplasty With Patellar Resurfacing? A Radiographic Review.

    PubMed

    Matz, Jacob; Howard, James L; Morden, David J; MacDonald, Steven J; Teeter, Matthew G; Lanting, Brent A

    2017-03-01

    Patellofemoral joint biomechanics contribute to anterior knee pain, instability, and dysfunction following total knee arthroplasty (TKA). Information about specific factors leading to anterior knee pain and dysfunction is currently limited. Changes in patellofemoral joint offset (PFO) refers to a mismatch between the preoperative and postoperative anteroposterior geometry of the patellofemoral joint. It remains unclear whether these changes lead to adverse outcomes in TKA. A retrospective radiographic review of 970 knees pre-TKA and post-TKA was completed to correlate the radiographic and clinical outcomes of changing the PFO using a posterior-stabilized single knee design with patellar resurfacing. A total of 970 patients were reviewed. Postoperatively, the anterior femoral offset, anteroposterior femoral size, and anterior patellar offset were changed in 40%, 60%, and 71% of knees, respectively, compared to preoperative values. The Western Ontario and McMasters Osteoarthritis Index total score as well as subscale scores for pain and function were not significantly affected by an increase or decrease in PFO. Similarly, Knee Society Scores and range of motion were not significantly affected. Increased anterior patellar offset was, however, associated with increased postoperative patellar tilt. Postoperative patellar tilt was not correlated with adverse patient satisfaction scores or loss of range of motion. Changes in PFO (decreased, maintained, or increased) are common post-TKA and are not associated with a difference in clinical outcomes. Increases in anterior patellar offset led to increased patellar tilt, which was not associated with adverse patient satisfaction scores. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. The sacroiliac joint: anatomy, physiology and clinical significance.

    PubMed

    Forst, Stacy L; Wheeler, Michael T; Fortin, Joseph D; Vilensky, Joel A

    2006-01-01

    The sacroiliac joint (SIJ) is a putative source of low back pain. The objective of this article is to provide clinicians with a concise review of SIJ structure and function, diagnostic indicators of SIJ-mediated pain, and therapeutic considerations. The SIJ is a true diarthrodial joint with unique characteristics not typically found in other diarthrodial joints. The joint differs with others in that it has fibrocartilage in addition to hyaline cartilage, there is discontinuity of the posterior capsule, and articular surfaces have many ridges and depressions. The sacroiliac joint is well innervated. Histological analysis of the sacroiliac joint has verified the presence of nerve fibers within the joint capsule and adjoining ligaments. It has been variously described that the sacroiliac joint receives its innervation from the ventral rami of L4 and L5, the superior gluteal nerve, and the dorsal rami of L5, S1, and S2, or that it is almost exclusively derived from the sacral dorsal rami. Even though the sacroiliac joint is a known putative source of low back and lower extremity pain, there are few findings that are pathognomonic of sacroiliac joint pain. The controlled diagnostic blocks utilizing the International Association for the Study of Pain (IASP) criteria demonstrated the prevalence of pain of sacroiliac joint origin in 19% to 30% of the patients suspected to have sacroiliac joint pain. Conservative management includes manual medicine techniques, pelvic stabilization exercises to allow dynamic postural control, and muscle balancing of the trunk and lower extremities. Interventional treatments include sacroiliac joint, intra-articular joint injections, radiofrequency neurotomy, prolotherapy, cryotherapy, and surgical treatment. The evidence for intra-articular injections and radiofrequency neurotomy has been shown to be limited in managing sacroiliac joint pain.

  12. Medium-term outcomes and complications after total replacement of the temporomandibular joint. Prospective outcome analysis after 3 and 5 years.

    PubMed

    Gruber, E A; McCullough, J; Sidebottom, A J

    2015-05-01

    In this prospective analysis, we assess the medium-term benefits, efficacy, and safety of the TMJ Concepts joint replacement system in the United Kingdom. Outcome measures of pain, maximum mouth opening, and diet were recorded preoperatively and at intervals up to 3 and 5 years. All patients who had replacement temporomandibular joints (TMJ) within a 6-year period were included. A total of 58 patients (84 joints) were followed up for 3 years (mean age 47, range 19-72) and 26 (42 joints) for 5 years (mean age 46, range 27-70). The female to male ratio was 52:6 at 3 years and 23:3 at 5 years. The most common diagnosis was degenerative disease, and the mean number of previous TMJ procedures was 2.4 (range 0-14). There were significant improvements in pain scores (7.4 reduced to 0.6 at 3 years and 0.8 at 5 years), maximum mouth opening (21.0-35.5mm at 3 years and 23.8-33.7mm at 5 years), and dietary scores (4.1-9.7 at 3 years and 3.7-9.6 at 5 years). Revision operations were required in 2 patients (not included in the outcome data) for biofilm infection of the prosthesis secondary to local infection in the head and neck. One patient had weakness of the temporal branch of the facial nerve that needed correction. TMJ replacement is an effective form of management for an irreparably damaged joint, particularly in cases of ankylosis. It lessens pain and improves function with minimal long-term morbidity. Copyright © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  13. [Feasibility and accuracy of ultrasound-guided methodology in the examination of lumbar spine facet joints].

    PubMed

    Wen, Chuan-Bing; Li, Yong-Zhong; Tang, Qin-Qin; Sun, Lin; Xiao, Hong; Yang, Bang-Xiang; Song, Li; Liu, Hui

    2013-03-01

    To investigate the feasibility, accuracy of B ultrasound in the examination of joint space of lumbar spine facet joints compared with CT scan. Ten healthy adult volunteers were enrolled. The joint space of lumbar facet joints was measured by ultrasound. To identify the spinal levels, the posterior parasagittal sonograms were obtained at levels L1 to S1. The lumbar facet joints were delineated with the help of transverse sonograms at each level. Meanwhile, the lumbar facet joints were evaluated by spiral CT on the same plane, reformatted to 1-mm axial slices. A total of 88 lumbar facet joints from L1 to S1 were clearly visualized in the 10 volunteers. Both ultrasound and CT measurements showed the same average depth and lateral distance of lumbar facet joint space (P > 0.05). The lumbar facet joint space can be accurately demonstrated by ultrasound.

  14. Nikolaus Rüdinger (1832-1896), His Description of Joint Innervation in 1857, and the History of Surgical Joint Denervation.

    PubMed

    Gohritz, Andreas; Kaiser, Erich; Guggenheim, Merlin; Dellon, Arnold Lee

    2018-01-01

     Selective joint denervation has become a reliable palliative treatment, especially for painful joints in the upper and lower extremity.  This article highlights the life and work of Nikolaus Rüdinger (1832-1896) who first described joint innervation which became the basis of later techniques of surgical joint denervation. The historical evolution of this method is outlined.  Rüdinger made a unique career from apprentice barber to military surgeon and anatomy professor in Munich, Germany. His first description of articular innervation of temporomandibular, shoulder, elbow, wrist, finger, sacroiliac, hip, knee, ankle, foot, and toe joints in 1857 stimulated the subsequent history of surgical joint denervation. Comparing his investigations with modern joint denervation methods, developed by pioneers like Albrecht Wilhelm or A. Lee Dellon, shows his great exactitude and anatomical correspondence despite different current terminology. Clinical series of modern surgical joint denervations reveal success rates of up to 80% with reliable long-term results.  The history of joint denervation with Rüdinger as its important protagonist offers inspiring insights into the evolution of surgical techniques and exemplifies the value of descriptive functional anatomy, even if surgical application may not have been realized until a century later. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  15. 30 CFR 36.24 - Engine joints.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Engine joints. 36.24 Section 36.24 Mineral... Construction and Design Requirements § 36.24 Engine joints. (a) Cylinder head. The joint between the cylinder head and block of the engine shall be fitted with a metal or metal-clad gasket satisfactory to MSHA...

  16. 30 CFR 36.24 - Engine joints.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Engine joints. 36.24 Section 36.24 Mineral... Construction and Design Requirements § 36.24 Engine joints. (a) Cylinder head. The joint between the cylinder head and block of the engine shall be fitted with a metal or metal-clad gasket satisfactory to MSHA...

  17. 30 CFR 36.24 - Engine joints.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Engine joints. 36.24 Section 36.24 Mineral... Construction and Design Requirements § 36.24 Engine joints. (a) Cylinder head. The joint between the cylinder head and block of the engine shall be fitted with a metal or metal-clad gasket satisfactory to MSHA...

  18. 30 CFR 36.24 - Engine joints.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Engine joints. 36.24 Section 36.24 Mineral... Construction and Design Requirements § 36.24 Engine joints. (a) Cylinder head. The joint between the cylinder head and block of the engine shall be fitted with a metal or metal-clad gasket satisfactory to MSHA...

  19. 30 CFR 36.24 - Engine joints.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Engine joints. 36.24 Section 36.24 Mineral... Construction and Design Requirements § 36.24 Engine joints. (a) Cylinder head. The joint between the cylinder head and block of the engine shall be fitted with a metal or metal-clad gasket satisfactory to MSHA...

  20. 46 CFR 385.38 - Joint funding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false Joint funding. 385.38 Section 385.38 Shipping MARITIME... AGREEMENTS REGULATIONS General Policies § 385.38 Joint funding. (a) Pursuant to section 10(c) of the Act, MarAd is authorized to participate in joint funded projects with other Federal agencies in any funding...

  1. 46 CFR 385.38 - Joint funding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false Joint funding. 385.38 Section 385.38 Shipping MARITIME... AGREEMENTS REGULATIONS General Policies § 385.38 Joint funding. (a) Pursuant to section 10(c) of the Act, MarAd is authorized to participate in joint funded projects with other Federal agencies in any funding...

  2. 46 CFR 385.38 - Joint funding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Joint funding. 385.38 Section 385.38 Shipping MARITIME... AGREEMENTS REGULATIONS General Policies § 385.38 Joint funding. (a) Pursuant to section 10(c) of the Act, MarAd is authorized to participate in joint funded projects with other Federal agencies in any funding...

  3. 46 CFR 385.38 - Joint funding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Joint funding. 385.38 Section 385.38 Shipping MARITIME... AGREEMENTS REGULATIONS General Policies § 385.38 Joint funding. (a) Pursuant to section 10(c) of the Act, MarAd is authorized to participate in joint funded projects with other Federal agencies in any funding...

  4. 46 CFR 385.38 - Joint funding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Joint funding. 385.38 Section 385.38 Shipping MARITIME... AGREEMENTS REGULATIONS General Policies § 385.38 Joint funding. (a) Pursuant to section 10(c) of the Act, MarAd is authorized to participate in joint funded projects with other Federal agencies in any funding...

  5. Descriptive epidemiology of joint injuries in Thoroughbred racehorses in training.

    PubMed

    Reed, S R; Jackson, B F; Mc Ilwraith, C W; Wright, I M; Pilsworth, R; Knapp, S; Wood, J L N; Price, J S; Verheyen, K L P

    2012-01-01

    No large scale epidemiological studies have previously quantified the occurrence of carpal, metacarpo- and metatarsophalangeal (MCP/MTP) joint injuries in Thoroughbred racehorses. To develop an objective classification system for carpal and MCP/MTP joint injuries and estimate the incidence of these injuries in young Thoroughbreds in flat race training. In a prospective cohort study, data on daily exercise and veterinary-diagnosed carpal and MCP/MTP joint injuries were collected from Thoroughbreds monitored since starting training as yearlings, for up to 2 years. Cases were classified in one of 4 categories: 1) localised to a carpal or MCP/MTP joint based on clinical examination and/or diagnostic analgesia; no diagnostic imaging performed; 2) localised to a carpal or MCP/MTP joint based on clinical examination and/or diagnostic analgesia; radiographs taken but no abnormalities detected; 3) evidence of abnormality of subchondral bone and/or articular margin(s) on diagnostic imaging and 4) evidence of discontinuity of the articular surface on diagnostic imaging. Incidence rates and rate ratios were estimated using Poisson regression, adjusting for trainer-level clustering. A total of 647 horses from 13 trainers throughout England contributed 7785 months at risk of joint injury. One-hundred-and-eighty-four cases of carpal (n = 82) or MCP/MTP (n = 102) joint injury were reported in 165 horses and classified in Category 1 (n = 21), Category 2 (n = 21), Category 3 (n = 72) or Category 4 (n = 70). The overall joint injury rate was 1.8 per 100 horse months (95% CI = 1.2, 2.8); rates did not differ significantly between 2- and 3-year-olds but females sustained Category 1 injuries at triple the rate of males (P = 0.03). Joint injury rates differed significantly between trainers (P<0.001) and there was trainer variation in anatomical site and severity of injury. Carpal and MCP/MTP joint injuries are an important cause of morbidity in Thoroughbred racehorses. Identification of

  6. The Treatment of Joint Pain with Intra-articular Pulsed Radiofrequency.

    PubMed

    Schianchi, Pietro M; Sluijter, Menno E; Balogh, Susan E

    2013-09-01

    The intra-articular (IA) application of pulsed radiofrequency (PRF) for pain in small and large joints represents a recent development that has proven to be effective in many cases. We performed a retrospective study of 89 such procedures in 57 consecutive patients with chronic articular pain. The aim of this retrospective study is to evaluate the effectiveness of intraarticular PRF in a group of 57 consecutive patients with chronic joint pain. Patients with intractable joint pain for more than 6 months were treated with IA PRF 40-45V for 10-15 min in small joints and 60V for 15 min in large joints using fluoroscopic confirmation of correct needle position. A total of 28 shoulders, 40 knees, 10 trapezio-metacarpal, and 11 first metatarso-phalangeal joints were treated. Results were evaluated at 1, 2, and 5 months. The procedure was repeated after 1 month in 10 patients with initial suboptimal results. Success was defined as a reduction of pain score by at least 50%. All groups showed significant reductions in pain scores at all three follow-up visits. Success rates were higher in small joints (90% and 82%, respectively) than large ones (64% and 60%, respectively). Interestingly, IA PRF was successful in 6 out of 10 patients who had undergone previous surgery, including 3 with prosthetic joint replacement and in 6 of the 10 repeated procedures. There were no significant adverse effects or complications. IA PRF induced significant pain relief of long duration in a majority of our patients with joint pain. The exact mechanism is unclear, but may be related to the exposure of immune cells to low-strength RF fields, inducing an anti-inflammatory effect. The success rate appears to be highest in small joints. We recommend additional research including control groups to further investigate and clarify this method; our data suggest that it may represent a useful modality in the treatment of arthrogenic pain.

  7. Development Requirements for Spacesuit Elbow Joint

    NASA Technical Reports Server (NTRS)

    Peters, Benjamin

    2017-01-01

    Functional Requirements for spacesuit elbow joint:1) The system is a conformal, single-axis spacesuit pressurized joint that encloses the elbow joint of the suited user and uses a defined interface to connect to the suit systems on either side of the joint.2) The system shall be designed to bear the loads incurred from the internal pressure of the system, as well as the expected loads induced by the user while enabling the user move the joint through the required range of motion. The joint torque of the system experienced by the user shall remain at or below the required specification for the entire range of motion.3) The design shall be constructed, at a minimum, as a two-layer system. The internal, air-tight layer shall be referred to as the bladder, and the layer on the unpressurized side of the bladder shall be referred to as the restraint. The design of the system may include additional features or layers, such as axial webbing, to meet the overall requirements of the design.

  8. The relationships between instrumented measurements of ankle and knee ligamentous laxity and generalized joint laxity.

    PubMed

    Pearsall, A W; Kovaleski, J E; Heitman, R J; Gurchiek, L R; Hollis, J M

    2006-03-01

    The purpose of this study was to evaluate whether lower extremity joint laxity is a function of a particular joint and/or a generalizable characteristic (trait) of the person. Validated instrumented measurements of ankle and knee joint-specific laxity in the same individual were correlated to determine whether a relationship exists. In addition, ankle and knee joint-specific laxity were correlated with generalized joint laxity using the modified Beighton mobility index. Fifty-seven male and female athletes were studied. We examined dominant ankle laxity using an ankle arthrometer and dominate knee anterior laxity using the KT 2000. The dominant ankle was loaded in anteroposterior (AP) drawer and inversion-eversion (I-E) rotation. Laxity was measured as total AP displacement (millimeters) after +/-125 N of applied force and total I-E rotation (degrees) was measured after +/-4 N x m of applied torque. The dominant knee was loaded with an anterior drawer and laxity (millimeters) was measured after manual maximum displacement. Non-significant correlations were observed among the test variables for generalized joint laxity (0.21 to 0.37; P>0.05) and instrumented ankle and knee joint laxity (0.19 to 0.21; P>0.05). When examined by gender, no statistically significant correlations (0.05 to 0.40; P>0.05) were found for either generalized laxity or instrumented ankle and knee joint laxity. These results imply that ankle and knee joint laxity are joint-specific and not generalizable.

  9. Inflammation is more distinct in temporomandibular joint osteoarthritis compared to the knee joint.

    PubMed

    Vos, Lukas M; Kuijer, Roel; Huddleston Slater, James J R; Bulstra, Sjoerd K; Stegenga, Boudewijn

    2014-01-01

    Most of the current understanding of articular cartilage maintenance and degradation is derived from large load-bearing synovial joints, in particular the knee joint. The aim of this study was to identify valuable degradation markers for cartilage degradation in the temporomandibular joint (TMJ) by comparing the relative concentrations of carboxyterminal telopeptides of collagen types I and II (CTX-I and CTX-II), cartilage oligomeric matrix protein (COMP), and prostaglandin E2 (PGE2) in synovial fluid (SF) of TMJ and knee joints with cartilage degradation. In this cross-sectional comparative study, participants were recruited from the University Medical Center Groningen, The Netherlands. Patients with TMJ osteoarthritis were compared with patients with knee osteoarthritis. The outcome variables were the relative SF concentrations of CTX-I, CTX-II, COMP, and PGE2. An independent samples Mann-Whitney U test was used to compare the relative concentrations. Thirty consecutive patients (9 male, 21 female; mean age, 40.1 yr; standard deviation, 15.3 yr) with TMJ osteoarthritis and 31 consecutive patients (20 male, 11 female; mean age, 37.4 yr; standard deviation, 13.7 yr) who were scheduled for arthroscopy of the knee joint participated in this study. Significant differences were found between relative concentrations of COMP (P = .000) and PGE2 (P = .005), and no significant differences were found between relative concentrations of CTX-I (P = .720) and CTX-II (P = .242). Relative SF concentrations of COMP and PGE2 showed significant differences between the TMJ and the knee joint, suggesting that there are differences in pathophysiology and that the inflammatory component may be more distinct in the TMJ. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  10. Inpatient Consults and Complications During Primary Total Joint Arthroplasty in a Bundled Care Model.

    PubMed

    Baumgartner, Billy T; Karas, Vasili; Kildow, Beau J; Cunningham, Daniel J; Klement, Mitchell R; Green, Cindy L; Attarian, David E; Seyler, Thorsten M

    2018-04-01

    The Centers for Medicare and Medicaid Services (CMS) are implementing changes in hospital reimbursement models for total joint arthroplasty (TJA), moving to value-based bundled payments from the fee-for-service model. The purpose of this study is to identify consults and complications during the perioperative period that increase financial burden. We combined CMS payment data for inpatient, professional, and postoperative with retrospective review of patients undergoing primary TJA and developed profiles of patients included in the Comprehensive Care for Joint Replacement bundle undergoing TJA. Statistical comparison of episode inpatient events and payments was conducted. Multiple regression analysis was adjusted for length of stay, disposition, and Charlson-Deyo comorbidity profile. Median total payment was $21,577.36, which exceeded the median bundle target payment of $20,625.00. Adjusted analyses showed that psychiatry consults (increase of $73,123.32; P < .001), internal medicine consults ($5789.38; P ≤ .001), pulmonary embolism ($35,273.68; P < .001), intensive care unit admission ($14,078.37; P < .001), and deep vein thrombosis ($9471.26; P = .019) resulted in increased payments using multivariate analysis adjusted for length of stay, Charlson-Deyo comorbidities, and discharge disposition. Patients with inpatient complications such as pulmonary embolism and/or deep vein thrombosis, intensive care unit admission, and medical/psychiatric consultation exceeded the CMS target. Although study results showed typical complication rates, acute inpatient consultation significantly increased utilization beyond the CMS target even when adjusted for length of stay, patient comorbidities, and discharge. Needed medical care should continue to be a priority for inpatients, and allowance for individual outliers should be considered in policy discussions. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Combined use of intravenous and topical versus intravenous tranexamic acid in primary total joint arthroplasty: A meta-analysis of randomized controlled trials.

    PubMed

    Zhang, Xue-Qin; Ni, Jie; Ge, Wei-Hong

    2017-02-01

    To compare the safety and efficacy of combined use of intravenous and topical tranexamic acid with that of intravenous tranexamic acid in primary total joint arthroplasty. Literature was searched in PubMed, Cochrane Library, Embase, Medline, and China National Knowledge Infrastructure databases. Only randomized controlled trials were included in our study. Data were using fixed-effects or random-effects models with standard mean differences and risk ratios for continuous and dichotomous variables, respectively. Seven randomized controlled trials encompassing 683 patients were retrieved for this meta-analysis. Outcomes showed that when compared with intravenous tranexamic acid, combined use of intravenous and topical tranexamic acid could significantly reduce total blood loss by a mean of 138.70 mL [95% confidence interval (CI): -196.14 to -81.26, p < 0.001], transfusion rates (risk ratio 0.42, 95% CI: 0.2 to 0.85, p < 0.001). No significant difference in the occurrence of deep vein thrombosis, pulmonary embolism was found between the two groups. This meta-analysis indicated that comparing with only intravenous tranexamic acid, combined use of intravenous and topical tranexamic acid can significantly reduce blood loss and transfusion rate in primary total joint arthroplasty without increasing the risk of thrombotic complications. Therefore, we suggest that tranexamic acid should be intravenously combined with topically administered in primary total joint arthroplasty. Copyright © 2016. Published by Elsevier Ltd.

  12. The Joint Chiefs of Staff Video Collections

    Science.gov Websites

    Senior Enlisted Advisor Joint Staff History Joint Staff Inspector General Joint Staff Structure Origin of J8 | Force Structure, Resources & Assessment Contact Home : Media : Videos Featured Videos Gen

  13. Shoulder Joint For Protective Suit

    NASA Technical Reports Server (NTRS)

    Kosmo, Joseph J.; Smallcombe, Richard D.

    1994-01-01

    Shoulder joint allows full range of natural motion: wearer senses little or no resisting force or torque. Developed for space suit, joint offers advantages in protective garments for underwater work, firefighting, or cleanup of hazardous materials.

  14. 49 CFR 213.121 - Rail joints.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the rail on which it is applied. (b) If a joint bar on Classes 3 through 5 track is cracked, broken... at each joint in Classes 2 through 5 track, and with at least one bolt in Class 1 track. (e) In the... accommodate expansion and contraction due to temperature variations. When no-slip, joint-to-rail contact...

  15. Joint Chiefs of Staff > Directorates > J3 | Operations

    Science.gov Websites

    Joint Staff Structure Joint Staff Inspector General Origin of Joint Concepts U.S. Code | Joint Chiefs of J8 | Force Structure, Resources & Assessment Contact J3 Operations Home : Directorates : J3

  16. Experimental cryo-irrigation of the knee joint.

    PubMed

    Chen, S C; Helal, B; Revell, P A; Brocklehurst, R; Currey, H L

    1986-10-01

    Experiments have been carried out to test the feasibility of using cryo-irrigation as a means of ablating the synovium in the rheumatoid knee joint. Cryo-irrigation was performed by a cooling machine and pump, which circulated cold 200/10 centistoke (cSt) silicone through the knee joint of rabbits anaesthetised with intravenous (IV) 'Saffan'. Fluid left the joint at -5 to -10 degrees C. Sixteen normal New Zealand rabbits received cryo-irrigation of one knee joint for 10-20 minutes and were killed at one day, and one, two, and 12 weeks thereafter. Judged by radioactive sulphate incorporation there was no impairment of chondrocyte function in the articular cartilage of irrigated joints. Histological examination showed mild synovitis and some loss of staining of superficial cartilage in 6/16 irrigated joints (v 1/16 control joints). Similar treatment of rabbit joints in which the Glynn model of synovitis had been induced showed marked reduction of synovitis 14-45 days after silicone treatment. Nine of 26 animals in which synovitis was induced in both knees and cryo-irrigation performed in one knee died either immediately postoperatively or during the next week. These deaths remain unexplained. A single dog received cryo-irrigation of one knee (-6 to -9 degrees C for 22 min) and remained perfectly well up to sacrifice at six months, when the joint appeared histologically completely normal.

  17. Managed care and critical pathway development: the joint replacement experience.

    PubMed

    Benham, A J

    1999-01-01

    This article examines the economic, social, ethical, and political issues affecting total joint replacement patients in a managed care environment. Using general systems theory as a framework, it examines the interrelated historical events that have shaped the development of both joint replacement procedures and managed care, and discusses the extent to which these two phenomena have been mutually influential. Specifically, the article examines the initial development, implementation, and continuing evolution of clinical pathways as an easily identified and relatively discrete manifestation of managed care for the joint replacement population. While the overall impact of managed care is beyond the scope of this presentation, it is hoped that a focus on the practical application of clinical pathways to joint replacement will allow some general principles to emerge that may be useful for both patients and practitioners operating in other aspects of the managed care environment.

  18. The effects of progressive lateralization of the joint center of rotation of reverse total shoulder implants.

    PubMed

    Costantini, Oren; Choi, Daniel S; Kontaxis, Andreas; Gulotta, Lawrence V

    2015-07-01

    There has been a renewed interest in lateralizing the center of rotation (CoR) in implants used in reverse shoulder arthroplasty. The aim of this study was to determine the sensitivity of lateralization of the CoR on the glenohumeral joint contact forces, muscle moment arms, torque across the bone-implant interface, and the stability of the implant. A 3-dimensional virtual model was used to investigate how lateralization affects deltoid muscle moment arm and glenohumeral joint contact forces. This model was virtually implanted with 5 progressively lateralized reverse shoulder prostheses. The joint contact loads and deltoid moment arms were calculated for each lateralization over the course of 3 simulated standard humerothoracic motions. Lateralization of the CoR leads to an increase in the overall joint contact forces across the glenosphere. Most of this increased loading occurred through compression, although increases in anterior/posterior and superior/inferior shear were also observed. Moment arms of the deltoid consistently decreased with lateralization. Bending moments at the implant interface increased with lateralization. Progressive lateralization resulted in improved stability ratios. Lateralization results in increased joint loading. Most of that loading occurs through compression, although there were also increases in shear forces. Anterior/posterior shear is currently not accounted for in implant fixation studies, leaving its effect on implant fixation unknown. Future studies should incorporate shear forces into their models to more accurately assess fixation methods. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  19. Temporomandibular joint involvement caused by Borrelia Burgdorferi.

    PubMed

    Lesnicar, Gorazd; Zerdoner, Danijel

    2007-12-01

    Lyme borreliosis is an endemic disease in Slovenia with an incidence of around 150 patients per 100,000 inhabitants. Although the large joints are most typically affected in Lyme borreliosis, there are also periods of disease activity with arthritis or arthralgias involving smaller joints, including the temporo-mandibular joint. During the years between 2000 and 2003, two patients with Lyme borreliosis affecting the temporo-mandibular joints were treated. The patients presented with fatigue and pain in diverse muscle groups accompanied by arthralgia, which was most pronounced in the temporomandibular joint area. None of the patients were febrile or had joint effusions. Both patients were examined by means of biochemical and serological examinations for Borrelia burgdorferi using ELISA assay and Western blot test (both for IgM and IgG), plain radiographs, MR and CT scans, and scinti-scan of the temporo-mandibular joints They both had positive serum markers for an acute B. burgdorferi infection and were treated with intravenous ceftriaxone. None of the patients had clinical or laboratory signs of chronic Lyme disease activity two and four years following therapy, respectively. Roentgenographic and nuclear magnetic resonance imaging of the temporo-mandibular joints had not shown any persistent sign of acute inflammation. There are only few reports of patients with manifest temporo-mandibular joint involvement of Lyme borreliosis in the literature. This report emphasizes the importance of differential diagnosis of acute temporo-mandibular joint arthralgia, of early diagnosis of Lyme borreliosis, and of the necessity for prompt antibiotic treatment.

  20. Tribo-electrochemical characterization of metallic biomaterials for total joint replacement.

    PubMed

    Diomidis, N; Mischler, S; More, N S; Roy, Manish

    2012-02-01

    Knee and hip joint replacement implants involve a sliding contact between the femoral component and the tibial or acetabular component immersed in body fluids, thus making the metallic parts susceptible to tribocorrosion. Micro-motions occur at points of fixation leading to debris and ion release by fretting corrosion. β-Titanium alloys are potential biomaterials for joint prostheses due to their biocompatibility and compatibility with the mechanical properties of bone. The biotribocorrosion behavior of Ti-29Nb-13Ta-4.6Zr was studied in Hank's balanced salt solution at open circuit potential and at an applied potential in the passive region. Reciprocating sliding tribocorrosion tests were carried out against technical grade ultra high molecular weight polyethylene, while fretting corrosion tests were carried out against alumina. The wear of the alloy is insignificant when sliding against polyethylene. However, depassivation does take place, but the tested alloy showed an ability to recover its passive state during sliding. The abrasivity of the alloy depends on the electrochemical conditions of the contact, while the wear of polyethylene proceeds through third body formation and material transfer. Under fretting corrosion conditions recovery of the passive state was also achieved. In a fretting contact wear of the alloy proceeds through plastic deformation of the bulk material and wear resistance depends on the electrochemical conditions. Copyright © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  1. Elbow Joint Fatigue and Bench-Press Training

    PubMed Central

    Huang, Yen-Po; Chou, You-Li; Chen, Feng-Chun; Wang, Rong-Tyai; Huang, Ming-Jer; Chou, Paul Pei-Hsi

    2014-01-01

    Context: Bench-press exercises are among the most common form of training exercise for the upper extremity because they yield a notable improvement in both muscle strength and muscle endurance. The literature contains various investigations into the effects of different bench-press positions on the degree of muscle activation. However, the effects of fatigue on the muscular performance and kinetics of the elbow joint are not understood fully. Objective: To investigate the effects of fatigue on the kinetics and myodynamic performance of the elbow joint in bench-press training. Design: Controlled laboratory study. Setting: Motion research laboratory. Patients or Other Participants: A total of 18 physically healthy male students (age = 19.6 ± 0.8 years, height = 168.7 ± 5.5 cm, mass = 69.6 ± 8.6 kg) participated in the investigation. All participants were right-hand dominant, and none had a history of upper extremity injuries or disorders. Intervention(s): Participants performed bench-press training until fatigued. Main Outcome Measure(s): Maximal possible number of repetitions, cycle time, myodynamic decline rate, elbow-joint force, and elbow-joint moment. Results: We observed a difference in cycle time in the initial (2.1 ± 0.42 seconds) and fatigue (2.58 ± 0.46 seconds) stages of the bench-press exercise (P = .04). As the participants fatigued, we observed an increase in the medial-lateral force (P = .03) and internal-external moment (P ≤ .04) acting on the elbow joint. Moreover, a reduction in the elbow muscle strength was observed in the elbow extension-flexion (P ≤ .003) and forearm supination-pronation (P ≤ .001) conditions. Conclusions: The results suggest that performing bench-press exercises to the point of fatigue increases elbow-joint loading and may further increase the risk of injury. Therefore, when clinicians design bench-press exercise regimens for general athletic training, muscle strengthening, or physical rehabilitation, they should

  2. Anatomy of the pelvic joints--a review.

    PubMed

    Dietrichs, E

    1991-01-01

    In adults, after the os ilium, os ischii and os pubis have joined together by ossification to form the os coxae, there is usually one joint between the hip bones ventrally (the pubic symphysis) and several more complex joints between the hip bones and os sacrum dorsally (sacroiliac, "axial sacroiliac" and accessory sacroiliac joints). These joints carry the weight of the upper part of the body, but they shall also enable pelvic distention during labour. Pathological conditions in these joints are common, and increased knowledge concerning their normal antomy is important for better understanding of these conditions.

  3. Management of acromioclavicular joint injuries.

    PubMed

    Li, Xinning; Ma, Richard; Bedi, Asheesh; Dines, David M; Altchek, David W; Dines, Joshua S

    2014-01-01

    Acromioclavicular joint injuries are among the most common shoulder girdle injuries in athletes and most commonly result from a direct force to the acromion with the arm in an adducted position. Acromioclavicular joint injuries often present with associated injuries to the glenohumeral joint, including an increased incidence of superior labrum anterior posterior (SLAP) tears that may warrant further evaluation and treatment. Anteroposterior stability of the acromioclavicular joint is conferred by the capsule and acromioclavicular ligaments, of which the posterior and superior ligaments are the strongest. Superior-inferior stability is maintained by the coracoclavicular (conoid and trapezoid) ligaments. Type-I or type-II acromioclavicular joint injuries have been treated with sling immobilization, early shoulder motion, and physical therapy, with favorable outcomes. Return to activity can occur when normal shoulder motion and strength are obtained and the shoulder is asymptomatic as compared with the contralateral normal extremity. The management of type-III injuries remains controversial and is individualized. While a return to the previous level of functional activity with nonsurgical treatment has been documented in a number of case series, surgical reduction and coracoclavicular ligament reconstruction has been associated with a favorable outcome and can be considered in patients who place high functional demands on their shoulders or in athletes who participate in overhead sports. Surgical management is indicated for high-grade (≥type IV) acromioclavicular joint injuries to achieve anatomic reduction of the acromioclavicular joint, reconstruction of the coracoclavicular ligaments, and repair of the deltotrapezial fascia. Outcomes after surgical reconstruction of the coracoclavicular ligaments have been satisfactory with regard to achieving pain relief and return to functional activities, but further improvements in the biomechanical strength of these

  4. Longitudinal joint specifications and performance.

    DOT National Transportation Integrated Search

    2012-08-01

    Deterioration of longitudinal joints is widely recognized as one of the major factors contributing to failure of asphalt pavements. Finding : ways to improve the durability of longitudinal joints will lead to improved service lives and lower life cyc...

  5. Photonic Waveguide Choke Joint with Non-Absorptive Loading

    NASA Technical Reports Server (NTRS)

    Wollack, Edward J. (Inventor); U-Yen, Kongpop (Inventor); Chuss, David T. (Inventor)

    2016-01-01

    A waveguide choke joint includes a first array of pillars positioned on a substrate, each pillar in the first array of pillars having a first size and configured to receive an input plane wave at a first end of the choke joint. The choke joint has a second end configured to transmit the input plane wave away from the choke joint. The choke joint further includes a second array of pillars positioned on the substrate between the first array of pillars and the second end of the choke joint. Each pillar in the second array of pillars has a second size. The choke joint also has a third array of pillars positioned on the substrate between the second array and the second end of the choke joint. Each pillar in the third array of pillars has a third size.

  6. Shading aboveground L-joint and lap-joint tests : comparison of white pine and sugar maple test assemblies

    Treesearch

    Carol A. Clausen; Daniel L. Lindner

    2011-01-01

    Five-year performance ratings are presented for two types of untreated, uncoated wood joints (L and lap) in aboveground tests under shaded conditions. The effect of shading on moisture entrapment in pine and maple L and lap joints was evaluated in a moderate decay zone (Madison, Wisconsin). Variations were observed between wood species, visual ratings, joint type,...

  7. Pressure relief and other joint rehabilitation techniques

    DOT National Transportation Integrated Search

    1987-02-01

    A study of four major concrete pavement joint rehabilitation techniques has been conducted, including: pressure relief joints, full-depth repairs, partial-depth repairs and joint resealing. The products of this research include the following for each...

  8. Hypermobile joints

    MedlinePlus

    ... Hypermobility syndrome Images Hypermobile joints References Ball JW, Dains JE, Flynn JA, Solomon BS, Stewart RW. Musculoskeletal system. In: Ball JW, Dains JE, Flynn JA, Solomon BS, Stewart RW, eds. ...

  9. Bone alterations are associated with ankle osteoarthritis joint pain

    PubMed Central

    Nakamura, Yukio; Uchiyama, Shigeharu; Kamimura, Mikio; Komatsu, Masatoshi; Ikegami, Shota; Kato, Hiroyuki

    2016-01-01

    The etiology of ankle osteoarthritis (OA) is largely unknown. We analyzed 24 ankle OA of 21 patients diagnosed by plain radiographs using magnetic resonance imaging (MRI). Ankle joint pain disappeared in 22 out of 24 joints by conservative treatment. MRI bone signal changes in and around the ankle joints were observed in 22 of 24 joints. Bone signal changes along the joint line were seen in 10 of 11 joints as a Kellgren-Lawrence (KL) grade of II to IV. Such signal changes were witnessed in only 4 of 13 joints with KL grade 0 or I. In the talocrural joint, bone alterations occurred in both tibia and talus bones through the joint line in cases of KL grade III or IV, while focal bone alterations were present in the talus only in KL grade I or II cases. Sixteen of 24 joints exhibited intraosseous bone signal changes, which tended to correspond to joint pain of any ankle OA stage. Our results suggest that bone alterations around the ankle joint might be one of the etiologies of OA and associated with ankle joint pain. PMID:26776564

  10. Bone alterations are associated with ankle osteoarthritis joint pain.

    PubMed

    Nakamura, Yukio; Uchiyama, Shigeharu; Kamimura, Mikio; Komatsu, Masatoshi; Ikegami, Shota; Kato, Hiroyuki

    2016-01-18

    The etiology of ankle osteoarthritis (OA) is largely unknown. We analyzed 24 ankle OA of 21 patients diagnosed by plain radiographs using magnetic resonance imaging (MRI). Ankle joint pain disappeared in 22 out of 24 joints by conservative treatment. MRI bone signal changes in and around the ankle joints were observed in 22 of 24 joints. Bone signal changes along the joint line were seen in 10 of 11 joints as a Kellgren-Lawrence (KL) grade of II to IV. Such signal changes were witnessed in only 4 of 13 joints with KL grade 0 or I. In the talocrural joint, bone alterations occurred in both tibia and talus bones through the joint line in cases of KL grade III or IV, while focal bone alterations were present in the talus only in KL grade I or II cases. Sixteen of 24 joints exhibited intraosseous bone signal changes, which tended to correspond to joint pain of any ankle OA stage. Our results suggest that bone alterations around the ankle joint might be one of the etiologies of OA and associated with ankle joint pain.

  11. Longitudinal joint treatment : construction report.

    DOT National Transportation Integrated Search

    2000-05-01

    Maine highways have been showing signs of longitudinal joint failure for a number of : years. In an effort to reduce the amount of joint failures the Maine Department of : Transportation (MDOT) is currently evaluating two projects. One project is mon...

  12. Boom and chassis articulation joints

    NASA Technical Reports Server (NTRS)

    Murphy, Joel T., Jr.; Nguyen, Vien; Turner, Bonnie; Wheeler, Bobby; Williams, Kimberlyn

    1992-01-01

    The primary goal of our design project was to develop articulation joints for the chassis and boom of the proof-of-concept lunar vehicle. This is an ongoing project and the work of previous student groups was extensively reviewed. Some of the ideas generated are variations of past proposals. Although the project is funded by NASA/USRA, it is totally a student design effort.

  13. A nondestructive, reproducible method of measuring joint reaction force at the distal radioulnar joint.

    PubMed

    Canham, Colin D; Schreck, Michael J; Maqsoodi, Noorullah; Doolittle, Madison; Olles, Mark; Elfar, John C

    2015-06-01

    To develop a nondestructive method of measuring distal radioulnar joint (DRUJ) joint reaction force (JRF) that preserves all periarticular soft tissues and more accurately reflects in vivo conditions. Eight fresh-frozen human cadaveric limbs were obtained. A threaded Steinmann pin was placed in the middle of the lateral side of the distal radius transverse to the DRUJ. A second pin was placed into the middle of the medial side of the distal ulna colinear to the distal radial pin. Specimens were mounted onto a tensile testing machine using a custom fixture. A uniaxial distracting force was applied across the DRUJ while force and displacement were simultaneously measured. Force-displacement curves were generated and a best-fit polynomial was solved to determine JRF. All force-displacement curves demonstrated an initial high slope where relatively large forces were required to distract the joint. This ended with an inflection point followed by a linear area with a low slope, where small increases in force generated larger amounts of distraction. Each sample was measured 3 times and there was high reproducibility between repeated measurements. The average baseline DRUJ JRF was 7.5 N (n = 8). This study describes a reproducible method of measuring DRUJ reaction forces that preserves all periarticular stabilizing structures. This technique of JRF measurement may also be suited for applications in the small joints of the wrist and hand. Changes in JRF can alter native joint mechanics and lead to pathology. Reliable methods of measuring these forces are important for determining how pathology and surgical interventions affect joint biomechanics. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  14. QM-8 field joint protection system, volume 7

    NASA Technical Reports Server (NTRS)

    Hale, Elgie

    1989-01-01

    The pre-launch functioning data of the Field Joint Protection System (JPS) used on QM-8 are presented. Also included is the post fire condition of the JPS components following the test firing of the motor. The JPS components are: field joint heaters; field joint sensors; field joint moisture seal; moisture seal kevlar retaining straps; field joint external extruded cork insulation; vent valve; power cables; and igniter heater.

  15. DEMES rotary joint: theories and applications

    NASA Astrophysics Data System (ADS)

    Wang, Shu; Hao, Zhaogang; Li, Mingyu; Huang, Bo; Sun, Lining; Zhao, Jianwen

    2017-04-01

    As a kind of dielectric elastomer actuators, dielectric elastomer minimum energy structure (DEMES) can realize large angular deformations by small voltage-induced strains, which make them an attractive candidate for use as biomimetic robotics. Considering the rotary joint is a basic and common component of many biomimetic robots, we have been fabricated rotary joint by DEMES and developed its performances in the past two years. In this paper, we have discussed the static analysis, dynamics analysis and some characteristics of the DEMES rotary joint. Based on theoretical analysis, some different applications of the DEMES rotary joint were presented, such as a flapping wing, a biomimetic fish and a two-legged walker. All of the robots are fabricated by DEMES rotary joint and can realize some basic biomimetic motions. Comparing with traditional rigid robot, the robot based on DEMES is soft and light, so it has advantage on the collision-resistant.

  16. Shear joint capability versus bolt clearance

    NASA Technical Reports Server (NTRS)

    Lee, H. M.

    1992-01-01

    The results of a conservative analysis approach into the determination of shear joint strength capability for typical space-flight hardware as a function of the bolt-hole clearance specified in the design are presented. These joints are comprised of high-strength steel fasteners and abutments constructed of aluminum alloys familiar to the aerospace industry. A general analytical expression was first arrived at which relates bolt-hole clearance to the bolt shear load required to place all joint fasteners into a shear transferring position. Extension of this work allowed the analytical development of joint load capability as a function of the number of fasteners, shear strength of the bolt, bolt-hole clearance, and the desired factor of safety. Analysis results clearly indicate that a typical space-flight hardware joint can withstand significant loading when less than ideal bolt hole clearances are used in the design.

  17. Design and fabrication of realistic adhesively bonded joints

    NASA Technical Reports Server (NTRS)

    Shyprykevich, P.

    1983-01-01

    Eighteen bonded joint test specimens representing three different designs of a composite wing chordwise bonded splice were designed and fabricated using current aircraft industry practices. Three types of joints (full wing laminate penetration, two side stepped; midthickness penetration, one side stepped; and partial penetration, scarfed) were analyzed using state of the art elastic joint analysis modified for plastic behavior of the adhesive. The static tensile fail load at room temperature was predicted to be: (1) 1026 kN/m (5860 1b/in) for the two side stepped joint; (2) 925 kN/m (5287 1b/in) for the one side stepped joint; and (3) 1330 kN/m (7600 1b/in) for the scarfed joint. All joints were designed to fail in the adhesive.

  18. Methicillin-Resistant and Methicillin-Sensitive Staphylococcus aureus Screening and Decolonization to Reduce Surgical Site Infection in Elective Total Joint Arthroplasty.

    PubMed

    Sporer, Scott M; Rogers, Thea; Abella, Linda

    2016-09-01

    Deep infection after elective total joint arthroplasty remains a devastating complication. Preoperative nasal swab screening for Staphylococcus aureus colonization and subsequent treatment of colonized patients is one proposed method to identify at-risk patients and decrease surgical site infections (SSIs). The purpose of this study was to determine whether a preoperative staphylococcus screening and treatment program would decrease the incidence of SSI in elective joint arthroplasty patients. Since January 2009, a total of 9690 patients having an elective joint arthroplasty were screened before surgery for Methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA) with nares swabs. All patients with positive nare colonization for MSSA and MRSA were treated with mupirocin and chlorhexidine gluconate showers for 5 days before surgery. MRSA patients received vancomycin preoperatively and were placed in contact isolation. All elective arthroplasty patients used chlorhexidine gluconate antiseptic cloths the evening prior and the day of surgery. Perioperative infection rates were compared from 1 year before implementation to 5 years after implementation of this screening protocol. SSI rates have decreased from 1.11% (prescreening) to 0.34% (nasal screening; P < .05) after initiation of the process. Staphylococcus was identified in 66.7% of the SSI infections before nasal screening and in 33.3% of the SSI after routine screening (P > .05). The addition of MRSA and/or MSSA nares screening along with a perioperative decolonization protocol has resulted in a decreased SSI rate by 69%. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Joint Airspace Control, Doctrine Update 10-06

    DTIC Science & Technology

    2010-05-20

    Doctrine Update 10-06 Joint Publication 3-52, Joint Airspace Control JP 3-52 provides joint doctrine for airspace control across the full range...identification, combined operations, and unmanned aerial vehicle If you want read the complete new doctrine document, dated 20 May 2010, click here: JP 3-52...Joint Airspace Control. For more information, visit the LeMay Center for Doctrine Development and Education, call us at DSN 493-7442, or e-mail

  20. Evaluation of Asphalt Bridge Deck Joint Systems.

    DOT National Transportation Integrated Search

    2009-12-01

    Asphaltic Plug Joint is an expansion joint that is used for new and rehabilitated bridges. It provides a smooth and watertight surface free of debris; and offers simple, easy and staged construction. Asphaltic plug joint can be repaired segmentally a...

  1. Joint imaging in polymyalgia rheumatica

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    O'Duffy, J.D.; Wahner, H.W.; Hunder, G.G.

    1976-08-01

    Technetium pertechnetate joint scintigrams were abnormal in 24 of 25 patients with polymyalgia rheumatica, in all 16 with rheumatoid arthritis, in 4 of 13 with nonarticular rheumatism, but in none of 26 control patients. Abnormal uptake in polymyalgia patients was commonest in shoulders and was less likely to be symmetric than in patients with rheumatoid arthritis, in whom distal joint abnormalities predominated. The pattern of abnormal uptake in polymyalgia rheumatica was not different in those with biopsy-proved giant cell arteritis. Correlation between symptoms and abnormal scintigrams was 72%, and abnormal uptake was present in 81% of joints of patients havingmore » physical abnormalities. Biopsy showed lymphocytic synovitis in the knee of one patient. After treatment the number of abnormal joints declined. These findings suggest that synovitis is common in polymyalgia rheumatica, and that it may account for some or most of the symptoms in this condition.« less

  2. Blood management and transfusion strategies in 600 patients undergoing total joint arthroplasty: an analysis of pre-operative autologous blood donation

    PubMed Central

    Perazzo, Paolo; Viganò, Marco; de Girolamo, Laura; Verde, Francesco; Vinci, Anna; Banfi, Giuseppe; Romagnoli, Sergio

    2013-01-01

    Background Blood loss during total joint arthroplasty strongly influences the time to recover after surgery and the quality of the recovery. Blood conservation strategies such as pre-operative autologous blood donation and post-operative cell salvage are intended to avoid allogeneic blood transfusions and their associated risks. Although widely investigated, the real effectiveness of these alternative transfusion practices remains controversial. Materials and methods The surgery reports of 600 patients undergoing total joint arthroplasty (312 hip and 288 knee replacements) were retrospectively reviewed to assess transfusion needs and related blood management at our institute. Evaluation parameters included post-operative blood loss, haemoglobin concentration measured at different time points, ASA score, and blood transfusion strategies. Results Autologous blood donation increased the odds of receiving a red blood cell transfusion. Reinfusion by a cell salvage system of post-operative shed blood was found to limit adverse effects in cases of severe post-operative blood loss. The peri-operative net decrease in haemoglobin concentration was higher in patients who had predeposited autologous blood than in those who had not. Discussion The strengths of this study are the high number of cases and the standardised procedures, all operations having been performed by a single orthopaedic surgeon and a single anaesthesiologist. Our data suggest that a pre-operative autologous donation programme may often be useless, if not harmful. Conversely, the use of a cell salvage system may be effective in reducing the impact of blood transfusion on a patient’s physiological status. Basal haemoglobin concentration emerged as a useful indicator of transfusion probability in total joint replacement procedures. PMID:23736922

  3. Hip and knee joint loading during vertical jumping and push jerking

    PubMed Central

    Cleather, Daniel J; Goodwin, Jon E; Bull, Anthony MJ

    2014-01-01

    Background The internal joint contact forces experienced at the lower limb have been frequently studied in activities of daily living and rehabilitation activities. In contrast, the forces experienced during more dynamic activities are not well understood, and those studies that do exist suggest very high degrees of joint loading. Methods In this study a biomechanical model of the right lower limb was used to calculate the internal joint forces experienced by the lower limb during vertical jumping, landing and push jerking (an explosive exercise derived from the sport of Olympic weightlifting), with a particular emphasis on the forces experienced by the knee. Findings The knee experienced mean peak loadings of 2.4-4.6 × body weight at the patellofemoral joint, 6.9-9.0 × body weight at the tibiofemoral joint, 0.3-1.4 × body weight anterior tibial shear and 1.0-3.1 × body weight posterior tibial shear. The hip experienced a mean peak loading of 5.5-8.4 × body weight and the ankle 8.9-10.0 × body weight. Interpretation The magnitudes of the total (resultant) joint contact forces at the patellofemoral joint, tibiofemoral joint and hip are greater than those reported in activities of daily living and less dynamic rehabilitation exercises. The information in this study is of importance for medical professionals, coaches and biomedical researchers in improving the understanding of acute and chronic injuries, understanding the performance of prosthetic implants and materials, evaluating the appropriateness of jumping and weightlifting for patient populations and informing the training programmes of healthy populations. PMID:23146164

  4. In Vivo Measurement of Glenohumeral Joint Contact Patterns

    NASA Astrophysics Data System (ADS)

    Bey, Michael J.; Kline, Stephanie K.; Zauel, Roger; Kolowich, Patricia A.; Lock, Terrence R.

    2009-12-01

    The objectives of this study were to describe a technique for measuring in-vivo glenohumeral joint contact patterns during dynamic activities and to demonstrate application of this technique. The experimental technique calculated joint contact patterns by combining CT-based 3D bone models with joint motion data that were accurately measured from biplane x-ray images. Joint contact patterns were calculated for the repaired and contralateral shoulders of 20 patients who had undergone rotator cuff repair. Significant differences in joint contact patterns were detected due to abduction angle and shoulder condition (i.e., repaired versus contralateral). Abduction angle had a significant effect on the superior/inferior contact center position, with the average joint contact center of the repaired shoulder 12.1% higher on the glenoid than the contralateral shoulder. This technique provides clinically relevant information by calculating in-vivo joint contact patterns during dynamic conditions and overcomes many limitations associated with conventional techniques for quantifying joint mechanics.

  5. ISHKS joint registry: A preliminary report.

    PubMed

    Pachore, Jawahir A; Vaidya, Shrinand V; Thakkar, Chandrasekhar J; Bhalodia, Haresh Kumar P; Wakankar, Hemant M

    2013-09-01

    Total knee arthroplasty (TKA) and total hip arthroplasty (THA) are the most widely practiced surgical options for arthritis all over the world and its application is rising in India. Indian Society of Hip and Knee Surgeons (ISHKS) has established a joints registry and has been collecting data for last 6 years. All members of ISHKS are encouraged to actively participate in the registry. A simple two page knee and hip form can be downloaded from the website www.ishks.com. The information collected includes patient demographics, indication for surgery, implant details and in case of revision arthroplasty: the details of implants removed and the cause of failure of primary arthroplasty. These forms are mailed to the central registry office and the data is fed in computerized registry. Data collection started in October 2006. Joint registry is a very important initiative of ISHKS and till date, have data of 34,478 TKAs and 3604 THAs, contributed by 42 surgeons across India. Some important observations have emerged. Data of 34,478 TKAs was assessed: These included 8612 males (25%) and 25,866 females (75%). Average age was 64.4 years (Osteoarthritis range: 45 to 88 years; Rheumatoid arthritis range: 22 to 74 years). Average body mass index was 29.1 (Range: 18.1 to 42.9). The indication for TKA was osteoarthritis in 33,444 (97%) and rheumatoid arthritis in 759 (2.2%). Total of 3604 THA procedures were recorded. These included 2162 (60%) male patients and 1442 (40%) female patients. Average age was 52 years (Range 17 to 85 years) and average BMI was 25.8 (Range: 17.3 to 38.5). The indications for THA was AVN in 49%. The registry will become more meaningful in years to come. Active participation of all arthroplasty surgeons across India is vital for the success of the joints registry.

  6. 49 CFR 236.752 - Joint, rail, insulated.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Joint, rail, insulated. 236.752 Section 236.752 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Joint, rail, insulated. A joint in which electrical insulation is provided between adjoining rails. ...

  7. Cadaveric Study of the Articular Branches of the Shoulder Joint.

    PubMed

    Eckmann, Maxim S; Bickelhaupt, Brittany; Fehl, Jacob; Benfield, Jonathan A; Curley, Jonathan; Rahimi, Ohmid; Nagpal, Ameet S

    This cadaveric study investigated the anatomic relationships of the articular branches of the suprascapular (SN), axillary (AN), and lateral pectoral nerves (LPN), which are potential targets for shoulder analgesia. Sixteen embalmed cadavers and 1 unembalmed cadaver, including 33 shoulders total, were dissected. Following dissections, fluoroscopic images were taken to propose an anatomical landmark to be used in shoulder articular branch blockade. Thirty-three shoulders from 17 total cadavers were studied. In a series of 16 shoulders, 16 (100%) of 16 had an intact SN branch innervating the posterior head of the humerus and shoulder capsule. Suprascapular sensory branches coursed laterally from the spinoglenoid notch then toward the glenohumeral joint capsule posteriorly. Axillary nerve articular branches innervated the posterolateral head of the humerus and shoulder capsule in the same 16 (100%) of 16 shoulders. The AN gave branches ascending circumferentially from the quadrangular space to the posterolateral humerus, deep to the deltoid, and inserting at the inferior portion of the posterior joint capsule. In 4 previously dissected and 17 distinct shoulders, intact LPNs could be identified in 14 (67%) of 21 specimens. Of these, 12 (86%) of 14 had articular branches innervating the anterior shoulder joint, and 14 (100%) of 14 LPN articular branches were adjacent to acromial branches of the thoracoacromial blood vessels over the superior aspect of the coracoid process. Articular branches from the SN, AN, and LPN were identified. Articular branches of the SN and AN insert into the capsule overlying the glenohumeral joint posteriorly. Articular branches of the LPN exist and innervate a portion of the anterior shoulder joint.

  8. Mechanical Behaviour of Bolted Joints Under Impact Rates of Loading

    DTIC Science & Technology

    2012-01-01

    Joints in Glass Fibre / Epoxy Laminates. Composites, Volume 16. No 2. Kolsky, H. (1949). An Investigation of the Mechanical Properties of Materials at...and equations 2.1 and 2, Figures 2.3, 2.4, and 2.5 were constructed to determine optimal specimen properties for later testing of bolted joints of...9.5 l/d=11.5 UNCLASSIFIED UNCLASSIFIED 2.5 Discussion Ideal specimen properties are high total equilibrium times, low equilibrium start times and

  9. Adaptive plasticity in mammalian masticatory joints

    NASA Astrophysics Data System (ADS)

    Ravosa, Matthew J.; Kunwar, Ravinder; Nicholson, Elisabeth K.; Klopp, Emily B.; Pinchoff, Jessie; Stock, Stuart R.; Stack, M. Sharon; Hamrick, Mark W.

    2006-08-01

    Genetically similar white rabbits raised on diets of different mechanical properties, as well as wild-type and myostatin-deficient mice raised on similar diets, were compared to assess the postweaning effects of elevated masticatory loads due to increased jaw-adductor muscle and bite forces on the proportions and properties of the mandibular symphysis and temporomandibular joint (TMJ). Microcomputed tomography (microCT) was used to quantify bone structure at a series of equidistant external and internal sites in coronal sections for a series of joint locations. Discriminant function analyses and non-parametric ANOVAs were used to characterize variation in biomineralization within and between loading cohorts. In both species, long-term excessive loading results in larger joint proportions, thicker articular and cortical bone, and increased biomineralization of hard tissues. Such adaptive plasticity appears designed to maintain the postnatal integrity of masticatory joint systems for a primary loading environment(s). This behavioral signal may be increasingly mitigated in older organisms by the interplay between adaptive and degradative joint tissue responses.

  10. Excluding joint probabilities from quantum theory

    NASA Astrophysics Data System (ADS)

    Allahverdyan, Armen E.; Danageozian, Arshag

    2018-03-01

    Quantum theory does not provide a unique definition for the joint probability of two noncommuting observables, which is the next important question after the Born's probability for a single observable. Instead, various definitions were suggested, e.g., via quasiprobabilities or via hidden-variable theories. After reviewing open issues of the joint probability, we relate it to quantum imprecise probabilities, which are noncontextual and are consistent with all constraints expected from a quantum probability. We study two noncommuting observables in a two-dimensional Hilbert space and show that there is no precise joint probability that applies for any quantum state and is consistent with imprecise probabilities. This contrasts with theorems by Bell and Kochen-Specker that exclude joint probabilities for more than two noncommuting observables, in Hilbert space with dimension larger than two. If measurement contexts are included into the definition, joint probabilities are not excluded anymore, but they are still constrained by imprecise probabilities.

  11. [Injuries of the acromioclavicular joint].

    PubMed

    Meeder, P J; Dannöhl, C

    1988-07-01

    The injuries of the acromio-clavicular joint require a differentiated diagnosis and treatment. The classification of the acromio-clavicular dislocations from grade I to grade III according to Tossy is proved. The diagnosis of a complete acromio-clavicular dislocation (Tossy III) is an indication for a surgical repair. Many and different methods are reported in the literature. 178 patients with a fresh acromio-clavicular dislocation (Typ Tossy II and III) were treated at the BG-Unfallklinik Tübingen from 1970 to 1987 by suturing the ligaments, inserting pins across the joint and tension wire bending. In old cases with Tossy III dislocation of the acromio-clavicular joint an oblique osteotomy combined with the reduction of the clavicle is recommended as a method of choice. The results of these procedures and there possible intra- and postoperative complications are reported. The incision along the clavicle quite often gives scar problems. Therefore the advantages of an arched incision across the acromio-clavicular joint is pointed out. Because of there biomechanical relationship fractures in the lateral third of the clavicle are similar to dislocations of the acromio-clavicular joint. The classification of these fractures according to Jäger, Buschle and Breitner allows a differentiated management of these lesions.

  12. Joint attention in Down syndrome: A meta-analysis.

    PubMed

    Hahn, Laura J; Loveall, Susan J; Savoy, Madison T; Neumann, Allie M; Ikuta, Toshikazu

    2018-07-01

    Some studies have indicated that joint attention may be a relative strength in Down syndrome (DS), but other studies have not. To conduct a meta-analysis of joint attention in DS to more conclusively determine if this is a relative strength or weakness when compared to children with typical development (TD), developmental disabilities (DD), and autism spectrum disorder (ASD). Journal articles published before September 13, 2016, were identified by using the search terms "Down syndrome" and "joint attention" or "coordinating attention". Identified studies were reviewed and coded for inclusion criteria, descriptive information, and outcome variables. Eleven studies (553 participants) met inclusion criteria. Children with DS showed similar joint attention as TD children and higher joint attention than children with DD and ASD. Meta-regression revealed a significant association between age and joint attention effect sizes in the DS vs. TD contrast. Joint attention appears to not be a weakness for children with DS, but may be commensurate with developmental level. Joint attention may be a relative strength in comparison to other skills associated with the DS behavioral phenotype. Early interventions for children with DS may benefit from leveraging joint attention skills. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Mechanical end joint system for structural column elements

    NASA Technical Reports Server (NTRS)

    Bush, H. G.; Wallsom, R. E. (Inventor)

    1982-01-01

    A mechanical end joint system, useful for the transverse connection of strut elements to a common node, comprises a node joint half with a semicircular tongue and groove, and a strut joint half with a semicircular tongue and groove. The two joint halves are engaged transversely and the connection is made secure by the inherent physical property characteristics of locking latches and/or by a spring-actioned shaft. A quick release mechanism provides rapid disengagement of the joint halves.

  14. Sensate Scaffolds Can Reliably Detect Joint Loading

    PubMed Central

    Bliss, C. L.; Szivek, J. A.; Tellis, B. C.; Margolis, D. S.; Schnepp, A. B.; Ruth, J. T.

    2008-01-01

    Treatment of cartilage defects is essential to the prevention of osteoarthritis. Scaffold-based cartilage tissue engineering shows promise as a viable technique to treat focal defects. Added functionality can be achieved by incorporating strain gauges into scaffolds, thereby providing a real-time diagnostic measurement of joint loading. Strain-gauged scaffolds were placed into the medial femoral condyles of 14 adult canine knees and benchtop tested. Loads between 75 and 130 N were applied to the stifle joints at 30°, 50°, and 70° of flexion. Strain-gauged scaffolds were able to reliably assess joint loading at all applied flexion angles and loads. Pressure sensitive films were used to determine joint surface pressures during loading and to assess the effect of scaffold placement on joint pressures. A comparison of peak pressures in control knees and joints with implanted scaffolds, as well as a comparison of pressures before and after scaffold placement, showed that strain-gauged scaffold implantation did not significantly alter joint pressures. Future studies could possibly use strain-gauged scaffolds to clinically establish normal joint loads and to determine loads that are damaging to both healthy and tissue-engineered cartilage. Strain-gauged scaffolds may significantly aid the development of a functional engineered cartilage tissue substitute as well as provide insight into the native environment of cartilage. PMID:16941586

  15. Joint pain

    MedlinePlus

    ... both rest and exercise are important. Warm baths, massage, and stretching exercises should be used as often ... Does keeping the joint elevated help? Do medicines, massage, or applying heat reduce the pain? What other ...

  16. Evaluation of traction stirrup distraction technique to increase the joint space of the shoulder joint in the dog: A cadaveric study.

    PubMed

    Devesa, V; Rovesti, G L; Urrutia, P G; Sanroman, F; Rodriguez-Quiros, J

    2015-06-01

    The objective of this study was to evaluate technical feasibility and efficacy of a joint distraction technique by traction stirrup to facilitate shoulder arthroscopy and assess potential soft tissue damage. Twenty shoulders were evaluated radiographically before distraction. Distraction was applied with loads from 40 N up to 200 N, in 40 N increments, and the joint space was recorded at each step by radiographic images. The effects of joint flexion and intra-articular air injection at maximum load were evaluated. Radiographic evaluation was performed after distraction to evaluate ensuing joint laxity. Joint distraction by traction stirrup technique produces a significant increase in the joint space; an increase in joint laxity could not be inferred by standard and stress radiographs. However, further clinical studies are required to evaluate potential neurovascular complications. A wider joint space may be useful to facilitate arthroscopy, reducing the likelihood for iatrogenic damage to intra-articular structures. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Pain from intra-articular NGF or joint injury in the rat requires contributions from peptidergic joint afferents.

    PubMed

    Kras, Jeffrey V; Weisshaar, Christine L; Pall, Parul S; Winkelstein, Beth A

    2015-09-14

    Non-physiological stretch of the cervical facet joint's capsular ligament induces persistent behavioral hypersensitivity and spinal neuronal hyperexcitability via an intra-articular NGF-dependent mechanism. Although that ligament is innervated by nociceptors, it is unknown if a subpopulation is exclusively responsible for the behavioral and spinal neuronal responses to intra-articular NGF and/or facet joint injury. This study ablated joint afferents using the neurotoxin saporin targeted to neurons involved in either peptidergic ([Sar(9),Met (O2)(11)]-substance P-saporin (SSP-Sap)) or non-peptidergic (isolectin B4-saporin (IB4-Sap)) signaling to investigate the contributions of those neuronal populations to facet-mediated pain. SSP-Sap, but not IB4-Sap, injected into the bilateral C6/C7 facet joints 14 days prior to an intra- articular NGF injection prevents NGF-induced mechanical and thermal hypersensitivity in the forepaws. Similarly, only SSP- Sap prevents the increase in mechanical forepaw stimulation- induced firing of spinal neurons after intra-articular NGF. In addition, intra-articular SSP-Sap prevents both behavioral hypersensitivity and upregulation of NGF in the dorsal root ganglion after a facet joint distraction that normally induces pain. These findings collectively suggest that disruption of peptidergic signaling within the joint may be a potential treatment for facet pain, as well as other painful joint conditions associated with elevated NGF, such as osteoarthritis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  18. Virtual trajectories, joint stiffness, and changes in the limb natural frequency during single-joint oscillatory movements.

    PubMed

    Latash, M L

    1992-07-01

    In the framework of the equilibrium-point hypothesis, virtual trajectories and patterns of joint stiffness were reconstructed during voluntary single-joint oscillatory movements in the elbow joint at a variety of frequencies and against two inertial loads. At low frequencies, virtual trajectories were in-phase with the actual joint trajectories. Joint stiffness changed at a doubled frequency. An increase in movement frequency and/or inertial load led to an increase in the difference between the peaks of the actual and virtual trajectories and in both peak and averaged values of joint stiffness. At a certain, critical frequency, virtual trajectory was nearly flat. Further increase in movement frequency led to a 180 degree phase shift between the actual and virtual trajectories. The assessed values of the natural frequency of the system "limb + manipulandum" were close to the critical frequencies for both low and high inertial loads. Peak levels and integrals of the electromyograms of two flexor and two extensor muscles changed monotonically with movement frequency without any special behavior at the critical frequencies. Nearly flat virtual trajectories at the natural frequency make physical sense as hypothetical control signals, unlike the electromyographic recordings, since a system at its natural frequency requires minimal central interference. Modulation of joint stiffness is assumed to be an important adaptive mechanism attenuating difference between the system's natural frequency and desired movement frequency. Virtual trajectory is considered a behavioral observable. Phase transitions between the virtual and actual trajectories are illustrations of behavioral discontinuities introduced by slow changes in a higher level control parameter, movement frequency. Relative phase shift between these two trajectories may be considered an order parameter.

  19. Effect of Nd:YAG laser beam welding on weld morphology and mechanical properties of Ti-6Al-4V butt joints and T-joints

    NASA Astrophysics Data System (ADS)

    Kashaev, Nikolai; Ventzke, Volker; Fomichev, Vadim; Fomin, Fedor; Riekehr, Stefan

    2016-11-01

    A Nd:YAG single-sided laser beam welding process study for Ti-6Al-4V butt joints and T-joints was performed to investigate joining techniques with regard to the process-weld morphology relationship. An alloy compatible filler wire was used to avoid underfills and undercuts. The quality of the butt joints and T-joints was characterized in terms of weld morphology, microstructure and mechanical properties. Joints with regular shapes, without visible cracks, pores, and geometrical defects were achieved. Tensile tests revealed high joint integrity in terms of strength and ductility for both the butt joint and T-joint geometries. Both the butt joints and T-joints showed base material levels of strength. The mechanical performance of T-joints was also investigated using pull-out tests. The performance of the T-joints in such tests was sensitive to the shape and morphology of the welds. Fracture always occurred in the weld without any plastic deformation in the base material outside the weld.

  20. Progressive Damage Analysis of Bonded Composite Joints

    NASA Technical Reports Server (NTRS)

    Leone, Frank A., Jr.; Girolamo, Donato; Davila, Carlos G.

    2012-01-01

    The present work is related to the development and application of progressive damage modeling techniques to bonded joint technology. The joint designs studied in this work include a conventional composite splice joint and a NASA-patented durable redundant joint. Both designs involve honeycomb sandwich structures with carbon/epoxy facesheets joined using adhesively bonded doublers.Progressive damage modeling allows for the prediction of the initiation and evolution of damage within a structure. For structures that include multiple material systems, such as the joint designs under consideration, the number of potential failure mechanisms that must be accounted for drastically increases the complexity of the analyses. Potential failure mechanisms include fiber fracture, intraply matrix cracking, delamination, core crushing, adhesive failure, and their interactions. The bonded joints were modeled using highly parametric, explicitly solved finite element models, with damage modeling implemented via custom user-written subroutines. Each ply was discretely meshed using three-dimensional solid elements. Layers of cohesive elements were included between each ply to account for the possibility of delaminations and were used to model the adhesive layers forming the joint. Good correlation with experimental results was achieved both in terms of load-displacement history and the predicted failure mechanism(s).

  1. Benign joint hypermobility syndrome in soldiers; what is the effect of military training courses on associated joint instabilities?

    PubMed

    Azma, Kamran; Mottaghi, Peyman; Hosseini, Alireza; Abadi, Hossein Hassan; Nouraei, Mohammad Hadi

    2014-07-01

    Hypermobile joints are joints with beyond normal range of motion and may be associated with joint derangements. This study aimed to evaluate the prevalence of benign joint hypermobility syndrome (BJHS) among soldiers and effect of training courses on related joint instabilities. In a prospective cohort study on 721 soldiers of Iran Army in Isfahan in 2013 the prevalence of joint hypermobility was obtained by using Beighton criteria. Soldiers divided in two groups of healthy and suffered based on their scores. The prevalence of ankle sprain, shoulder and temporomandibular joint (TMJ) dislocations identified before beginning service by history-taking and reviewing paraclinical documents. After 3 months of military training, a recent occurrence of mentioned diseases was revaluated in two groups. The collected data were analyzed using SPSS-20 software using Independent-T and Chi-square tests. The frequency of BJHS before military training was 29.4%. After passing military training period, the incidence of ankle sprain was significantly higher in suffered group achieving the minimum Beighton score (BS) of 4 (4.3%, P = 0.03), 5 (5.5%, P = 0.005) and also 6 out of 9 (6.5%, P = 0.01). The incidence of TMJ dislocation was not significantly different based on a minimum score of 4, while it was higher in suffered group when considering the score of 5 (2.1%) and 6 (2.6%) for discrimination of two groups (P = 0.03). There was no significant difference between two groups in case of shoulder dislocation anyway. Military training can increase the incidence of ankle sprains and TMJ dislocations in hypermobility persons with higher BS in comparison with healthy people. Therefore, screening of joint hypermobility may be useful in identifying individuals at increased risk for joint instabilities.

  2. Cryotherapy impairs knee joint position sense.

    PubMed

    Oliveira, R; Ribeiro, F; Oliveira, J

    2010-03-01

    The effects of cryotherapy on joint position sense are not clearly established; however it is paramount to understand its impact on peripheral feedback to ascertain the safety of using ice therapy before resuming exercise on sports or rehabilitation settings. Thus, the aim of the present study was to determine the effects of cryotherapy, when applied over the quadriceps and over the knee joint, on knee position sense. This within-subjects repeated-measures study encompassed fifteen subjects. Knee position sense was measured by open kinetic chain technique and active positioning at baseline and after cryotherapy application. Knee angles were determined by computer analysis of the videotape images. Twenty-minute ice bag application was applied randomly, in two sessions 48 h apart, over the quadriceps and the knee joint. The main effect for cryotherapy application was significant (F (1.14)=7.7, p=0.015) indicating an increase in both absolute and relative angular errors after the application. There was no significant main effect for the location of cryotherapy application, indicating no differences between the application over the quadriceps and the knee joint. In conclusion, cryotherapy impairs knee joint position sense in normal knees. This deleterious effect is similar when cryotherapy is applied over the quadriceps or the knee joint. Georg Thieme Verlag KG Stuttgart.New York.

  3. The relationship between target joints and direct resource use in severe haemophilia.

    PubMed

    O'Hara, Jamie; Walsh, Shaun; Camp, Charlotte; Mazza, Giuseppe; Carroll, Liz; Hoxer, Christina; Wilkinson, Lars

    2018-01-16

    Target joints are a common complication of severe haemophilia. While factor replacement therapy constitutes the majority of costs in haemophilia, the relationship between target joints and non drug-related direct costs (NDDCs) has not been studied. Data on haemophilia patients without inhibitors was drawn from the 'Cost of Haemophilia across Europe - a Socioeconomic Survey' (CHESS) study, a cost assessment in severe haemophilia A and B across five European countries (France, Germany, Italy, Spain, and the United Kingdom) in which 139 haemophilia specialists provided demographic and clinical information for 1285 adult patients. NDDCs were calculated using publicly available cost data, including 12-month ambulatory and secondary care activity: haematologist and other specialist consultant consultations, medical tests and examinations, bleed-related hospital admissions, and payments to professional care providers. A generalized linear model was developed to investigate the relationship between NDDCs and target joints (areas of chronic synovitis), adjusted for patient covariates. Five hundred and thirteen patients (42% of the sample) had no diagnosed target joints; a total of 1376 target joints (range 1-10) were recorded in the remaining 714 patients. Mean adjusted NDDCs for persons with no target joints were EUR 3134 (standard error (SE) EUR 158); for persons with one or more target joints, mean adjusted NDDCs were EUR 3913 (SE EUR 157; average mean effect EUR 779; p < 0.001). Our analysis suggests that the presence of one or more target joints has a significant impact on NDDCs for patients with severe haemophilia, ceteris paribus. Prevention and management of target joints should be an important consideration of managing haemophilia patients.

  4. Joint Enrollment: Fiscal Year 2016. Annual Report

    ERIC Educational Resources Information Center

    Division of Community Colleges and Workforce Preparation, Iowa Department of Education, 2017

    2017-01-01

    The Iowa Department of Education collects information on joint enrollment from Iowa's 15 community colleges. Jointly enrolled students are high school students enrolled in community college credit coursework. Most jointly enrolled students enroll through Senior Year Plus programs such as Postsecondary Enrollment Options (PSEO) and concurrent…

  5. 49 CFR 195.216 - Welding: Miter joints.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Welding: Miter joints. 195.216 Section 195.216 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... PIPELINE Construction § 195.216 Welding: Miter joints. A miter joint is not permitted (not including...

  6. 49 CFR 195.216 - Welding: Miter joints.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Welding: Miter joints. 195.216 Section 195.216 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... PIPELINE Construction § 195.216 Welding: Miter joints. A miter joint is not permitted (not including...

  7. 49 CFR 195.216 - Welding: Miter joints.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Welding: Miter joints. 195.216 Section 195.216 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... PIPELINE Construction § 195.216 Welding: Miter joints. A miter joint is not permitted (not including...

  8. 49 CFR 195.216 - Welding: Miter joints.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Welding: Miter joints. 195.216 Section 195.216 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... PIPELINE Construction § 195.216 Welding: Miter joints. A miter joint is not permitted (not including...

  9. 49 CFR 195.216 - Welding: Miter joints.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Welding: Miter joints. 195.216 Section 195.216 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... PIPELINE Construction § 195.216 Welding: Miter joints. A miter joint is not permitted (not including...

  10. [Viscosity determination of synovial fluids from the canine hip and elbow joint as well as the human knee joint].

    PubMed

    Helms, Gabriele; Rittmann, Pia; Wefstaedt, Patrick; Windhagen, Henning; Pressel, Thomas; Behrens, Bernd-Arno; Nolte, Ingo

    2008-01-01

    The development of pathological changes in both human and canine hip joints is mainly caused by a lack of synovial fluid lubrication. This results in an increased joint abrasion. Even after implantation of joint prosthesis, inadequate lubrication can lead to abrasion in the tribological pair. This can finally result in aseptic loosening of the prosthesis. In spite of the enormous number of studies that have been performed on human, only little knowledge about the tribological properties of the joints in dogs is available in the literature. For this reason the viscosities of synovial fluid, derived from physiological and pathologically changed canine elbow joints were measured. The viscosities were determined by the use of a cone-plate viscometer at different temperatures and shear rates. The obtained values were compared with the viscosity values of pathologically changed synovial fluids from human knee joints as well as with pathological samples from the canine hip joint. The results show that the viscosity values vary within a series of measurements and are inversely proportional to the temperature of the sample and the shear rate. The differences between the average viscosities of canine and human synovial fluids taken from pathologically changed joints are below 4% (22.5 s(-1) at theta1 = 25 degrees C). The findings of this study are being implemented in a FE-Model for the computation of actual forces in the hip joint during different movements. This would represent a contribution to an improved prosthetic treatment of canine and human hips.

  11. Effect of knee joint icing on knee extension strength and knee pain early after total knee arthroplasty: a randomized cross-over study.

    PubMed

    Holm, Bente; Husted, Henrik; Kehlet, Henrik; Bandholm, Thomas

    2012-08-01

    To investigate the acute effect of knee joint icing on knee extension strength and knee pain in patients shortly after total knee arthroplasty. A prospective, single-blinded, randomized, cross-over study. A fast-track orthopaedic arthroplasty unit at a university hospital. Twenty patients (mean age 66 years; 10 women) scheduled for primary unilateral total knee arthroplasty. The patients were treated on two days (day 7 and day 10) postoperatively. On one day they received 30 minutes of knee icing (active treatment) and on the other day they received 30 minutes of elbow icing (control treatment). The order of treatments was randomized. Maximal knee extension strength (primary outcome), knee pain at rest and knee pain during the maximal knee extensions were measured 2-5 minutes before and 2-5 minutes after both treatments by an assessor blinded for active or control treatment. The change in knee extension strength associated with knee icing was not significantly different from that of elbow icing (knee icing change (mean (1 SD)) -0.01 (0.07) Nm/kg, elbow icing change -0.02 (0.07) Nm/kg, P = 0.493). Likewise, the changes in knee pain at rest (P = 0.475), or knee pain during the knee extension strength measurements (P = 0.422) were not different between treatments. In contrast to observations in experimental knee effusion models and inflamed knee joints, knee joint icing for 30 minutes shortly after total knee arthroplasty had no acute effect on knee extension strength or knee pain.

  12. Measuring the effect of femoral malrotation on knee joint biomechanics for total knee arthroplasty using computational simulation

    PubMed Central

    Kang, K-T.; Koh, Y-G.; Son, J.; Kwon, O-R.; Baek, C.; Jung, S. H.

    2016-01-01

    Objectives Malrotation of the femoral component can result in post-operative complications in total knee arthroplasty (TKA), including patellar maltracking. Therefore, we used computational simulation to investigate the influence of femoral malrotation on contact stresses on the polyethylene (PE) insert and on the patellar button as well as on the forces on the collateral ligaments. Materials and Methods Validated finite element (FE) models, for internal and external malrotations from 0° to 10° with regard to the neutral position, were developed to evaluate the effect of malrotation on the femoral component in TKA. Femoral malrotation in TKA on the knee joint was simulated in walking stance-phase gait and squat loading conditions. Results Contact stress on the medial side of the PE insert increased with internal femoral malrotation and decreased with external femoral malrotation in both stance-phase gait and squat loading conditions. There was an opposite trend in the lateral side of the PE insert case. Contact stress on the patellar button increased with internal femoral malrotation and decreased with external femoral malrotation in both stance-phase gait and squat loading conditions. In particular, contact stress on the patellar button increased by 98% with internal malrotation of 10° in the squat loading condition. The force on the medial collateral ligament (MCL) and the lateral collateral ligament (LCL) increased with internal and external femoral malrotations, respectively. Conclusions These findings provide support for orthopaedic surgeons to determine a more accurate femoral component alignment in order to reduce post-operative PE problems. Cite this article: K-T. Kang, Y-G. Koh, J. Son, O-R. Kwon, C. Baek, S. H. Jung, K. K. Park. Measuring the effect of femoral malrotation on knee joint biomechanics for total knee arthroplasty using computational simulation. Bone Joint Res 2016;5:552–559. DOI: 10.1302/2046-3758.511.BJR-2016-0107.R1. PMID:28094763

  13. Mortuary Affairs in Joint Operations

    DTIC Science & Technology

    2006-06-05

    regulations, and doctrine. For the Chairman of the Joint Chiefs of Staff: WALTER L. SHARP Lieutenant General , USA Director, Joint Staff SUMMARY OF...Introduction ........................................................................................................... VII-1 • General Guidance...disposition of human remains ( PADD ); maintaining temporary interment sites including the recording of interment and disinterment actions; operation of the

  14. The effects of transcutaneous electrical nerve stimulation on joint position sense in patients with knee joint osteoarthritis.

    PubMed

    Shirazi, Zahra Rojhani; Shafaee, Razieh; Abbasi, Leila

    2014-10-01

    To study the effects of transcutaneous electrical nerve stimulation (TENS) on joint position sense (JPS) in knee osteoarthritis (OA) subjects. Thirty subjects with knee OA (40-60 years old) using non-random sampling participated in this study. In order to evaluate the absolute error of repositioning of the knee joint, Qualysis Track Manager system was used and sensory electrical stimulation was applied through the TENS device. The mean errors in repositioning of the joint, in two position of the knee joint with 20 and 60 degree angle, after applying the TENS was significantly decreased (p < 0.05). Application of TENS in subjects with knee OA could improve JPS in these subjects.

  15. Functional anatomy of the temporomandibular joint (I).

    PubMed

    Sava, Anca; Scutariu, Mihaela Monica

    2012-01-01

    Jaw movement is analyzed as the action between two rigid components jointed together in a particular way, the movable mandible against the stabilized cranium. Jaw articulation distinguishes form most other synovial joints of the body by the coincidence of certain characteristic features. Its articular surfaces are not covered by hyaline cartilage as elsewhere. The two jointed components carry teeth the shape, position and occlusion of which having a unique influence on specific positions and movements within the joint. A fibrocartilaginous disc is interposed between upper and lower articular surfaces; this disc compensates for the incongruities in opposing parts and allows sliding, pivoting, and rotating movements between the bony components. These are the reasons for our review of the functional anatomy of the temporomandibular joint.

  16. Joint health and functional ability in children with haemophilia who receive intensive replacement therapy.

    PubMed

    Groen, W; van der Net, J; Bos, K; Abad, A; Bergstrom, B-M; Blanchette, V S; Feldman, B M; Funk, S; Helders, P; Hilliard, P; Manco-Johnson, M; Petrini, P; Zourikian, N; Fischer, K

    2011-09-01

    Joint physical examination is an important outcome in haemophilia; however its relationship with functional ability is not well established in children with intensive replacement therapy. Boys aged 4-16 years were recruited from two European and three North American treatment centres. Joint physical structure and function was measured with the Haemophilia Joint Health Score (HJHS) while functional ability was measured with the revised Childhood Health Assessment Questionnaire (CHAQ₃₈. Two haemophilia-specific domains were created by selecting items of the CHAQ₃₈ that cover haemophilia-specific problems. Associations between CHAQ, HJHS, cumulative number of haemarthroses and age were assessed. A total of 226 subjects - mean 10.8 years old (SD 3.8) - participated; the majority (68%) had severe haemophilia. Most severe patients (91%) were on prophylactic treatment. Lifetime number of haemarthroses [median=5; interquartile range (IQR)=1-12] and total HJHS (median = 5; IQR=1-12) correlated strongly (ρ = 0.51). Total HJHS did not correlate with age and only weakly (ρ=-0.19) with functional ability scores (median=0; IQR=-0.06-0). Overall, haemarthroses were reported most frequently in the ankles. Detailed analysis of ankle joint health scores revealed moderate associations (ρ=0.3-0.5) of strength, gait and atrophy with lower extremity tasks (e.g. stair climbing). In this population, HJHS summating six joints did not perform as well as individual joint scores, however, certain elements of ankle impairment, specifically muscle strength, atrophy and gait associated significantly with functional loss in lower extremity activities. Mild abnormalities in ankle assessment by HJHS may lead to functional loss. Therefore, ankle joints may warrant special attention in the follow up of these children. © 2011 Blackwell Publishing Ltd.

  17. Finger-Jointed Wood Products.

    DTIC Science & Technology

    1981-04-01

    these melamines do not have the same Urea resins are generally marketed adhesives does not always develop resistance to weathering as do in liquid form...OF durable, colorless glueline is required. been developed for use in RF curing. FINGER JOINTS MelamineUrea Resins IN STRUCTURAL Melamine - urea resins ...finger duced either by dry blending urea and moplastic, softening if temperature is joints, strength is expressed as a melamine resins or by blending

  18. Composite SAR imaging using sequential joint sparsity

    NASA Astrophysics Data System (ADS)

    Sanders, Toby; Gelb, Anne; Platte, Rodrigo B.

    2017-06-01

    This paper investigates accurate and efficient ℓ1 regularization methods for generating synthetic aperture radar (SAR) images. Although ℓ1 regularization algorithms are already employed in SAR imaging, practical and efficient implementation in terms of real time imaging remain a challenge. Here we demonstrate that fast numerical operators can be used to robustly implement ℓ1 regularization methods that are as or more efficient than traditional approaches such as back projection, while providing superior image quality. In particular, we develop a sequential joint sparsity model for composite SAR imaging which naturally combines the joint sparsity methodology with composite SAR. Our technique, which can be implemented using standard, fractional, or higher order total variation regularization, is able to reduce the effects of speckle and other noisy artifacts with little additional computational cost. Finally we show that generalizing total variation regularization to non-integer and higher orders provides improved flexibility and robustness for SAR imaging.

  19. Evaluation of effects of different treatments for the wrist joints of subdominant hands using joint proprioception and writing time.

    PubMed

    Hu, Chunying; Huang, Qiuchen; Yu, Lili; Hu, Yue; Rongming, Xia; Li, Zhou; Xiaojiao, Fu; Gu, Rui; Cui, Yao; Ge, Meng; Xu, Yanfeng; Liu, Jianfeng

    2016-05-01

    [Purpose] The purpose of this study was to examine immediate effects of strength training and NJF distal resistance training in wrist joints by using writing time and evaluation of proprioception using the JPE test. [Subjects and Methods] The subjects were 12 young healthy people (24.2 ± 3.1 y, 169.7 ± 6.5 cm, 65.3 ± 12.6 kg). Two isotonic contraction techniques were applied on the wrist joint: wrist joint extension muscle strength training (MST) and the wrist joint extension pattern of NJF. The uppercase English alphabet writing time and joint position errors of the left upper limb were measured before and after one intervention session of MST and NJF. [Results] The decrease in errors in wrist extension angle repetition and the writing time represented the improvement resulting from NJF. [Conclusion] This result suggests that the subdominant hands wrist joint proprioception and writing function can be improved by NJF together with proximal resistance training.

  20. The joint in psoriatic arthritis.

    PubMed

    Mortezavi, Mahta; Thiele, Ralph; Ritchlin, Christopher

    2015-01-01

    Psoriatic arthritis (PsA), a chronic inflammatory joint disease associated with psoriasis, is notable for diversity in disease presentation, course and response to treatment. Equally varied are the types of musculoskeletal involvement which include peripheral and axial joint disease, dactylitis and enthesitis. In this review, we focus on the psoriatic joint and discuss pathways that underlie synovial, cartilage and bone inflammation and highlight key histopathologic features. The pivotal inflammatory mechanisms and pathobiology of PsA parallel findings in other forms of spondyloarthritis but are distinct from disease pathways described in rheumatoid synovitis and bone disease. The diagnosis of PsA from both a clinical and imaging perspective is also discussed.

  1. Change in collateral ligament length and tibiofemoral movement following joint line variation in TKA.

    PubMed

    Lin, Kun-Jhih; Wei, Hung-Wen; Huang, Chang-Hung; Liu, Yu-Liang; Chen, Wen-Chuan; McClean, Colin Joseph; Cheng, Cheng-Kung

    2016-08-01

    The primary intent of total knee arthroplasty is the restoration of normal knee kinematics, with ligamentous constraint being a key influential factor. Displacement of the joint line may lead to alterations in ligament attachment sites relative to knee flexion axis and variance of ligamentous constraints on tibiofemoral movement. This study aimed to investigate collaterals strains and tibiofemoral kinematics with different joint line levels. A previously validated knee model was employed to analyse the change in length of the collateral ligaments and tibiofemoral motion during knee flexion. The models shifted the joint line by 3 and 5 mm both proximally and distally from the anatomical level. The data were captured from full extension to flexion 135°. The elevated joint line revealed a relative increase in distance between ligament attachments for both collateral ligaments in comparison with the anatomical model. Also, tibiofemoral movement decreased with an elevation in the joint line. Conversely, lowering the joint line led to a significant decrease in distance between ligament attachments, but greater tibiofemoral motion. Elevation of the joint line would strengthen the capacity of collateral ligaments for knee motion constraint, whereas a distally shifted joint line might have the advantage of improving tibiofemoral movement by slackening the collaterals. It implies that surgeons can appropriately change the joint line position in accordance with patient's requirement or collateral tensions. A lowered joint line level may improve knee kinematics, whereas joint line elevation could be useful to maintain knee stability. V.

  2. Hip and knee joint loading during vertical jumping and push jerking.

    PubMed

    Cleather, Daniel J; Goodwin, Jon E; Bull, Anthony M J

    2013-01-01

    The internal joint contact forces experienced at the lower limb have been frequently studied in activities of daily living and rehabilitation activities. In contrast, the forces experienced during more dynamic activities are not well understood, and those studies that do exist suggest very high degrees of joint loading. In this study a biomechanical model of the right lower limb was used to calculate the internal joint forces experienced by the lower limb during vertical jumping, landing and push jerking (an explosive exercise derived from the sport of Olympic weightlifting), with a particular emphasis on the forces experienced by the knee. The knee experienced mean peak loadings of 2.4-4.6×body weight at the patellofemoral joint, 6.9-9.0×body weight at the tibiofemoral joint, 0.3-1.4×body weight anterior tibial shear and 1.0-3.1×body weight posterior tibial shear. The hip experienced a mean peak loading of 5.5-8.4×body weight and the ankle 8.9-10.0×body weight. The magnitudes of the total (resultant) joint contact forces at the patellofemoral joint, tibiofemoral joint and hip are greater than those reported in activities of daily living and less dynamic rehabilitation exercises. The information in this study is of importance for medical professionals, coaches and biomedical researchers in improving the understanding of acute and chronic injuries, understanding the performance of prosthetic implants and materials, evaluating the appropriateness of jumping and weightlifting for patient populations and informing the training programmes of healthy populations. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. 7 CFR 3405.7 - Joint project proposals.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Joint project proposals. 3405.7 Section 3405.7... AGRICULTURE HIGHER EDUCATION CHALLENGE GRANTS PROGRAM Program Description § 3405.7 Joint project proposals. Applicants are encouraged to submit joint project proposals as defined in § 3405.2(m), which address regional...

  4. Exercise and the Knee Joint.

    ERIC Educational Resources Information Center

    Clarke, H. Harrison, Ed.

    1976-01-01

    This report by the President's Council on Physical Fitness and Sports examines the effects of various forms of physical exercise on the knee joint which, because of its vulnerability, is especially subject to injury. Discussion centers around the physical characteristics of the joint, commonly used measurements for determining knee stability,…

  5. An in vitro simulation method for the tribological assessment of complete natural hip joints

    PubMed Central

    Fisher, John; Williams, Sophie

    2017-01-01

    The use of hip joint simulators to evaluate the tribological performance of total hip replacements is widely reported in the literature, however, in vitro simulation studies investigating the tribology of the natural hip joint are limited with heterogeneous methodologies reported. An in vitro simulation system for the complete natural hip joint, enabling the acetabulum and femoral head to be positioned with different orientations whilst maintaining the correct joint centre of rotation, was successfully developed for this study. The efficacy of the simulation system was assessed by testing complete, matched natural porcine hip joints and porcine hip hemiarthroplasty joints in a pendulum friction simulator. The results showed evidence of biphasic lubrication, with a non-linear increase in friction being observed in both groups. Lower overall mean friction factor values in the complete natural joint group that increased at a lower rate over time, suggest that the exudation of fluid and transition to solid phase lubrication occurred more slowly in the complete natural hip joint compared to the hip hemiarthroplasty joint. It is envisaged that this methodology will be used to investigate morphological risk factors for developing hip osteoarthritis, as well as the effectiveness of early interventional treatments for degenerative hip disease. PMID:28886084

  6. Interdependence of torque, joint angle, angular velocity and muscle action during human multi-joint leg extension.

    PubMed

    Hahn, Daniel; Herzog, Walter; Schwirtz, Ansgar

    2014-08-01

    Force and torque production of human muscles depends upon their lengths and contraction velocity. However, these factors are widely assumed to be independent of each other and the few studies that dealt with interactions of torque, angle and angular velocity are based on isolated single-joint movements. Thus, the purpose of this study was to determine force/torque-angle and force/torque-angular velocity properties for multi-joint leg extensions. Human leg extension was investigated (n = 18) on a motor-driven leg press dynamometer while measuring external reaction forces at the feet. Extensor torque in the knee joint was calculated using inverse dynamics. Isometric contractions were performed at eight joint angle configurations of the lower limb corresponding to increments of 10° at the knee from 30 to 100° of knee flexion. Concentric and eccentric contractions were performed over the same range of motion at mean angular velocities of the knee from 30 to 240° s(-1). For contractions of increasing velocity, optimum knee angle shifted from 52 ± 7 to 64 ± 4° knee flexion. Furthermore, the curvature of the concentric force/torque-angular velocity relations varied with joint angles and maximum angular velocities increased from 866 ± 79 to 1,238 ± 132° s(-1) for 90-50° knee flexion. Normalised eccentric forces/torques ranged from 0.85 ± 0.12 to 1.32 ± 0.16 of their isometric reference, only showing significant increases above isometric and an effect of angular velocity for joint angles greater than optimum knee angle. The findings reveal that force/torque production during multi-joint leg extension depends on the combined effects of angle and angular velocity. This finding should be accounted for in modelling and optimisation of human movement.

  7. Hypothyroidism: Does It Cause Joint Pain?

    MedlinePlus

    Hypothyroidism: Does it cause joint pain? Can hypothyroidism cause joint pain? I have hypothyroidism and have been experiencing severe arthritis-like pain in my shoulders and hips. Answers from Todd B. ...

  8. Phalangeal joints kinematics during ostrich (Struthio camelus) locomotion

    PubMed Central

    Ji, Qiaoli; Luo, Gang; Xue, Shuliang; Ma, Songsong; Li, Jianqiao

    2017-01-01

    The ostrich is a highly cursorial bipedal land animal with a permanently elevated metatarsophalangeal joint supported by only two toes. Although locomotor kinematics in walking and running ostriches have been examined, these studies have been largely limited to above the metatarsophalangeal joint. In this study, kinematic data of all major toe joints were collected from gaits with double support (slow walking) to running during stance period in a semi-natural setup with two selected cooperative ostriches. Statistical analyses were conducted to investigate the effect of locomotor gait on toe joint kinematics. The MTP3 and MTP4 joints exhibit the largest range of motion whereas the first phalangeal joint of the 4th toe shows the largest motion variability. The interphalangeal joints of the 3rd and 4th toes present very similar motion patterns over stance phases of slow walking and running. However, the motion patterns of the MTP3 and MTP4 joints and the vertical displacement of the metatarsophalangeal joint are significantly different during running and slow walking. Because of the biomechanical requirements, osctriches are likely to select the inverted pendulum gait at low speeds and the bouncing gait at high speeds to improve movement performance and energy economy. Interestingly, the motions of the MTP3 and MTP4 joints are highly synchronized from slow to fast locomotion. This strongly suggests that the 3rd and 4th toes really work as an “integrated system” with the 3rd toe as the main load bearing element whilst the 4th toe as the complementary load sharing element with a primary role to ensure the lateral stability of the permanently elevated metatarsophalangeal joint. PMID:28097064

  9. The association between parental interaction style and children’s joint engagement in families with toddlers with autism

    PubMed Central

    Patterson, Stephanie Y; Elder, Lauren; Gulsrud, Amanda; Kasari, Connie

    2014-01-01

    Purpose This study examines the relationship between parental interaction style (responsive vs directive) and child-initiated joint engagement within caregiver–child interactions with toddlers diagnosed with autism spectrum disorders. Method Videotaped interactions of 85 toddler–caregiver dyads were coded for child engagement and both parental responsiveness and directiveness. Results Altogether, children spent less than one-third of the interaction jointly engaged. After controlling for child characteristics, parental style was associated with the initiator (child or parent) of joint engagement. Specifically, responsiveness predicted total time in child-initiated joint engagement, while directiveness predicted total time in parent-initiated joint engagement. Children’s social behaviours were associated with child-initiated joint engagement. Discussion Social initiations are a key target for children with autism spectrum disorders. Results demonstrate that child initiations and global social behaviour ratings are associated with parental responsivity. Responsivity may be a critical factor to facilitate children’s initiations. PMID:24104518

  10. Self-aligning exoskeleton hip joint: Kinematic design with five revolute, three prismatic and one ball joint.

    PubMed

    Beil, Jonas; Marquardt, Charlotte; Asfour, Tamim

    2017-07-01

    Kinematic compatibility is of paramount importance in wearable robotic and exoskeleton design. Misalignments between exoskeletons and anatomical joints of the human body result in interaction forces which make wearing the exoskeleton uncomfortable and even dangerous for the human. In this paper we present a kinematically compatible design of an exoskeleton hip to reduce kinematic incompatibilities, so called macro- and micro-misalignments, between the human's and exoskeleton's joint axes, which are caused by inter-subject variability and articulation. The resulting design consists of five revolute, three prismatic and one ball joint. Design parameters such as range of motion and joint velocities are calculated based on the analysis of human motion data acquired by motion capture systems. We show that the resulting design is capable of self-aligning to the human hip joint in all three anatomical planes during operation and can be adapted along the dorsoventral and mediolateral axis prior to operation. Calculation of the forward kinematics and FEM-simulation considering kinematic and musculoskeletal constraints proved sufficient mobility and stiffness of the system regarding the range of motion, angular velocity and torque admissibility needed to provide 50 % assistance for an 80 kg person.

  11. Gait changes after using a temporomandibular joint exerciser in patients who underwent lower limb joint surgery

    PubMed Central

    Chung, Gu-Young; Choi, Geun-Seok; Shin, Ki-Young; Park, Joon-Soo

    2016-01-01

    [Purpose] The improvements in gait of the patients with lower limb disease who used a temporomandibular joint (TMJ) exerciser were verified. [Subjects and Methods] Eleven subjects were included. Their mean age was 53.2 years. The lower limb joint angles before and after using the TMJ exerciser were measured using a gait analyzer. Before the gait experiment, the TMJ exerciser setting process and one-leg stance balance test (OLST) were repeated until the balance maintenance time improved. [Results] Because of the OLST, the mean change in the body center point after the subjects used the exerciser improved from 5.76 mm to 4.20 mm. When the TMJ exerciser was used, the joint angle range of the subjects approached that of the normal individuals. [Conclusion] According to the gait experiments, the angles of the subjects’ hips, knees, and ankle joints approached to those of the normal individuals after the subjects used the TMJ exerciser; however, the results did not completely match. The changes in the hip, knee, and ankle joint angles were statistically significant, which confirm the usefulness of the TMJ exerciser. PMID:27313377

  12. Joint Problems

    MedlinePlus

    ... Help Related Topics Arthritis Join our e-newsletter! Aging & Health A to Z Joint Problems Basic Facts & ... April 2017 Posted: March 2012 © 2018 Health in Aging. All rights reserved. Feedback • Site Map • Privacy Policy • ...

  13. A Randomized, Clinical Trial of Preadmission Chlorhexidine Skin Preparation for Lower Extremity Total Joint Arthroplasty.

    PubMed

    Kapadia, Bhaveen H; Elmallah, Randa K; Mont, Michael A

    2016-12-01

    Periprosthetic infections are devastating postoperative complications of total joint arthroplasty (TJA), with native skin flora commonly identified as causative organisms. We compared 2% chlorhexidine gluconate-impregnated cloths to standard-of-care antiseptic bathing in patients before TJA, to evaluate periprosthetic infection risk at 1-year follow-up. This was a prospective, randomized, controlled trial at a single institution of patients undergoing hip or knee arthroplasty. Chlorhexidine-treated patients (275 arthroplasties) applied 2% chlorhexidine gluconate-impregnated cloths the night before and morning of admission. The standard-of-care cohort (279 arthroplasties) bathed with soap and water preadmission. Patients were excluded according to the following: (1) unable to comply with study requirements, (2) pregnant, (3) <18 years, (4) medical history of immunosuppression or steroid use, (5) chronic hepatitis B/C infection, (6) had infection around joint requiring surgery, or (7) chose not to participate. A total of 539 patients (554 arthroplasties) were included in the final population. There were no significant differences in American Society of Anesthesiologists grade, cut time, risk scores, or diabetes and smoking prevalence between cohorts (P > .05). A lower periprosthetic infection rate was found in the chlorhexidine cohort (0.4%) when compared to standard-of-care cohorts (2.9%). The infection odds ratio was 8.15 (95% confidence interval = 1.01-65.6; P = .049) for the standard-of-care cohort compared to the chlorhexidine cohort. No differences in assessed risk factors were found between groups. No severe adverse events were observed. Preoperative chlorhexidine cloth use decreased the risk of periprosthetic infection. This may be an appropriate antiseptic protocol to implement for patients undergoing lower extremity TJA. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Biomimetic-inspired joining of composite with metal structures: A survey of natural joints and application to single lap joints

    NASA Astrophysics Data System (ADS)

    Avgoulas, Evangelos Ioannis; Sutcliffe, Michael P. F.

    2014-03-01

    Joining composites with metal parts leads, inevitably, to high stress concentrations because of the material property mismatch. Since joining composite to metal is required in many high performance structures, there is a need to develop a new multifunctional approach to meet this challenge. This paper uses the biomimetics approach to help develop solutions to this problem. Nature has found many ingenious ways of joining dissimilar materials and making robust attachments, alleviating potential stress concentrations. A literature survey of natural joint systems has been carried out, identifying and analysing different natural joint methods from a mechanical perspective. A taxonomy table was developed based on the different methods/functions that nature successfully uses to attach dissimilar tissues (materials). This table is used to understand common themes or approaches used in nature for different joint configurations and functionalities. One of the key characteristics that nature uses to joint dissimilar materials is a transitional zone of stiffness in the insertion site. Several biomimetic-inspired metal-to-composite (steel-to-CFRP), adhesively bonded, Single Lap Joints (SLJs) were numerically investigated using a finite element analysis. The proposed solutions offer a transitional zone of stiffness of one joint part to reduce the material stiffness mismatch at the joint. An optimisation procedure was used to identify the variation in material stiffness which minimises potential failure of the joint. It was found that the proposed biomimetic SLJs reduce the asymmetry of the stress distribution along the adhesive area.

  15. Rheumatoid Arthritis Pain: Tips for Protecting Your Joints

    MedlinePlus

    Rheumatoid arthritis pain: Tips for protecting your joints Use these joint protection techniques to help you stay in control of your rheumatoid arthritis pain. By Mayo Clinic Staff Joint protection is ...

  16. Study of simple CFRP-metal joint failure

    NASA Astrophysics Data System (ADS)

    Cheng, Jingquan; Rodriguez, Antonio; Emerson, Nicolas; Symmes, Arthur

    2008-07-01

    In millimeter wavelength telescope design and construction, there have been a number of mysterious failures of simple CFRF-metal joints. Telescope designers have not had satisfactory interpretations of these failures. In this paper, factors which may influence the failure of joints are discussed. These include stress concentration, material creep, joint fatigue, reasons related to chemical process and manufacture process. Extrapolation formulas for material creep, joint fatigue, and differential thermal stresses are derived in this paper. Detailed chemical and manufacturing factors are also discussed. All these issues are the causes of a number of early failures under a loading which is significantly lower than the strength of adhesives used. For ensuring reliability of a precision instrument structure joint, the designer should have a thorough understanding of all these factors.

  17. Ultrasonic-assisted soldering of Cu/Ti joints

    NASA Astrophysics Data System (ADS)

    Cui, Wei; Wang, Chunyu; Li, Yuhang; Zhong, Tongtong; Yang, Jianguo; Bao, Yefeng

    2018-03-01

    Cu/Ti joints are expected to be used in various applications, while reliable joining method is still to be developed. It is commonly not possible to solder Ti alloys using Sn-based solder alloys because of their poor wettability. In this study, Sn-Ag-Cu soldering filler metal was used to joining TC4 titanium alloy and pure copper using ultrasonic-assisted soldering. The influence of different temperature and different ultrasonic time on the welded joint is studied and explored. Microstructure of the joints was investigated. Shear strength of the joints reached the maximum value, i.e. 38.2MPa. Relationship between the sonication parameters and the microstructure and strength of the joints was discussed. Thus, it is verified that dissimilar metal brazing of TC4 and copper is suitable for low temperature soldering.

  18. The relation between residual stress, interfacial structure and the joint property in the SiO2f/SiO2-Nb joints.

    PubMed

    Ma, Qiang; Li, Zhuo Ran; Yang, Lai Shan; Lin, Jing Huang; Ba, Jin; Wang, Ze Yu; Qi, Jun Lei; Feng, Ji Cai

    2017-06-23

    In order to achieve a high-quality joint between SiO 2f /SiO 2 and metals, it is necessary to address the poor wettability of SiO 2f /SiO 2 and the high residual stress in SiO 2f /SiO 2 -Nb joint. Here, we simultaneously realize good wettability and low residual stress in SiO 2f /SiO 2 -Nb joint by combined method of HF etching treatment and Finite Element Analysis (FEA). After etching treatment, the wettability of E-SiO 2f /SiO 2 was improved, and the residual stress in the joint was decreased. In order to better control the quality of joints, efforts were made to understand the relationship between surface structure of E-SiO 2f /SiO 2 and residual stress in joint using FEA. Based on the direction of FEA results, a relationship between residual stress, surface structure and joint property in the brazed joints were investigated by experiments. As well the FEA and the brazing test results both realized the high-quality joint of E-SiO 2f /SiO 2 -Nb and the shear strength of the joint reached 61.9 MPa.

  19. Joint Tactical Networks (JTN)

    DTIC Science & Technology

    2013-12-01

    Selected Acquisition Report (SAR) RCS: DD-A&T(Q&A)823-284 Joint Tactical Networks (JTN) As of FY 2015 President’s Budget... Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to a penalty for failing to comply with a collection...to 00-00-2013 4. TITLE AND SUBTITLE Joint Tactical Networks (JTN) 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S

  20. 26 CFR 20.2040-1 - Joint interests.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 14 2011-04-01 2010-04-01 true Joint interests. 20.2040-1 Section 20.2040-1... ESTATE TAX; ESTATES OF DECEDENTS DYING AFTER AUGUST 16, 1954 Gross Estate § 20.2040-1 Joint interests. (a... personal, and regardless of when the joint interests were created. Furthermore, it makes no difference that...

  1. Prosthetic Joint Infection

    PubMed Central

    Tande, Aaron J.

    2014-01-01

    SUMMARY Prosthetic joint infection (PJI) is a tremendous burden for individual patients as well as the global health care industry. While a small minority of joint arthroplasties will become infected, appropriate recognition and management are critical to preserve or restore adequate function and prevent excess morbidity. In this review, we describe the reported risk factors for and clinical manifestations of PJI. We discuss the pathogenesis of PJI and the numerous microorganisms that can cause this devastating infection. The recently proposed consensus definitions of PJI and approaches to accurate diagnosis are reviewed in detail. An overview of the treatment and prevention of this challenging condition is provided. PMID:24696437

  2. Sacroiliac Joint Interventions.

    PubMed

    Soto Quijano, David A; Otero Loperena, Eduardo

    2018-02-01

    Sacroiliac joint (SIJ) pain is an important cause of lower back problems. Multiple SIJ injection techniques have been proposed over the years to help in the diagnosis and treatment of this condition. However, the SIJ innervation is complex and variable, and truly intra-articular injections are sometimes difficult to obtain. Different sacroiliac joint injections have shown to provide pain relief in patients suffering this ailment. Various techniques for intraarticular injections, sacral branch blocks and radiofrequency ablation, both fluoroscopy guided and ultrasound guided are discussed in this paper. Less common techniques like prolotherapy, platelet rich plasma injections and botulism toxin injections are also discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Joint ventures: to pursue or not to pursue?

    PubMed

    Blaszyk, Michael D; Hill-Mischel, Jody

    2007-11-01

    Hospitals should carefully select joint venture partners. The joint venture evaluation process should involve a high-level screen of strategic opportunities. Hospitals should develop a full business plan for the joint venture.

  4. Detection of occult infection following total joint arthroplasty using sequential technetium-99m HDP bone scintigraphy and indium-111 WBC imaging

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Johnson, J.A.; Christie, M.J.; Sandler, M.P.

    1988-08-01

    Preoperative exclusion or confirmation of periprosthetic infection is essential for correct surgical management of patients with suspected infected joint prostheses. The sensitivity and specificity of (/sup 111/In)WBC imaging in the diagnosis of infected total joint prostheses was examined in 28 patients and compared with sequential (/sup 99m/Tc)HDP/(/sup 111/In)WBC scintigraphy and aspiration arthrography. The sensitivity of preoperative aspiration cultures was 12%, with a specificity of 81% and an accuracy of 58%. The sensitivity of (/sup 111/In)WBC imaging alone was 100%, with a specificity of 50% and an accuracy of 65%. When correlated with the bone scintigraphy and read as sequential (/supmore » 99m/Tc)HDP/(/sup 111/In)WBC imaging, the sensitivity was 88%, specificity 95%, and accuracy 93%. This study demonstrates that (/sup 111/In)WBC imaging is an extremely sensitive imaging modality for the detection of occult infection of joint prostheses. It also demonstrates the necessity of correlating (/sup 111/In)WBC images with (/sup 99m/Tc)HDP skeletal scintigraphy in the detection of occult periprosthetic infection.« less

  5. Physiological joint line total knee arthroplasty designs are especially sensitive to rotational placement - A finite element analysis.

    PubMed

    Moewis, Philippe; Checa, Sara; Kutzner, Ines; Hommel, Hagen; Duda, Georg N

    2018-01-01

    Mechanical and kinematical aligning techniques are the usual positioning methods during total knee arthroplasty. However, alteration of the physiological joint line and unbalanced medio-lateral load distribution are considered disadvantages in the mechanical and kinematical techniques, respectively. The aim of this study was to analyse the influence of the joint line on the strain and stress distributions in an implanted knee and their sensitivity to rotational mal-alignment. Finite element calculations were conducted to analyse the stresses in the PE-Inlay and the mechanical strains at the bone side of the tibia component-tibia bone interface during normal positioning of the components and internal and external mal-rotation of the tibial component. Two designs were included, a horizontal and a physiological implant. The loading conditions are based on internal knee joint loads during walking. A medialization of the stresses on the PE-Inlay was observed in the physiological implant in a normal position, accompanied by higher stresses in the mal-rotated positions. Within the tibia component-tibia bone interface, similar strain distributions were observed in both implant geometries in the normal position. However, a medialization of the strains was observed in the physiological implant in both mal-rotated conditions with greater bone volume affected by higher strains. Although evident changes due to mal-rotation were observed, the stresses do not suggest a local plastic deformation of the PE-Inlay. The strains values within most of the tibia component-tibia bone interface were in the physiological strain zone and no significant bone changes would be expected. The physiological cut on the articular aspect showed no detrimental effect compared to the horizontal implant.

  6. Experimental characterization of deployable trusses and joints

    NASA Technical Reports Server (NTRS)

    Ikegami, R.; Church, S. M.; Keinholz, D. A.; Fowler, B. L.

    1987-01-01

    The structural dynamic properties of trusses are strongly affected by the characteristics of joints connecting the individual beam elements. Joints are particularly significant in that they are often the source of nonlinearities and energy dissipation. While the joints themselves may be physically simple, direct measurement is often necessary to obtain a mathematical description suitable for inclusion in a system model. Force state mapping is a flexible, practical test method for obtaining such a description, particularly when significant nonlinear effects are present. It involves measurement of the relationship, nonlinear or linear, between force transmitted through a joint and the relative displacement and velocity across it. An apparatus and procedure for force state mapping are described. Results are presented from tests of joints used in a lightweight, composite, deployable truss built by the Boeing Aerospace Company. The results from the joint tests are used to develop a model of a full 4-bay truss segment. The truss segment was statically and dynamically tested. The results of the truss tests are presented and compared with the analytical predictions from the model.

  7. Joint hypermobility leading to osteoarthrosis and chondrocalcinosis.

    PubMed

    Bird, H A; Tribe, C R; Bacon, P A

    1978-06-01

    We have reviewed 21 adults referred to rheumatology clinic and considered to have generalised joint hypermobility by the criteria of Carter and Wilkinson (1964), modified by Beighton et al. (1973). They fell into two categories. 5 patients had a raised plasma viscosity (PV) and in each case a definite pathology was found to account for this, superimposed on hypermobile joints. The remaining 16 had a normal PV and this group was thought to represent the late natural history of hypermobility. 5 of these (aged 32 to 54 years) had no evidence of osteoarthrosis but the remaining 11 (aged 34 to 80 years) had widespread radiological osteoarthrosis. Synovial histology was obtained at arthroscopy in 6 of these patients and 4 (aged 60 to 75) had chondrocalcinosis. This previously undescribed finding may be the end result of hypermobile joints. Hypermobile patients with joint deformity (lax connective tissue), widespread synovial thickening (traumatic), and hot joint effusions (chondrocalcinosis) may mimic rheumatoid arthritis. They must be distinguished from patients who develop rheumatoid arthritis in hypermobile joints.

  8. Joint hypermobility leading to osteoarthrosis and chondrocalcinosis.

    PubMed Central

    Bird, H A; Tribe, C R; Bacon, P A

    1978-01-01

    We have reviewed 21 adults referred to rheumatology clinic and considered to have generalised joint hypermobility by the criteria of Carter and Wilkinson (1964), modified by Beighton et al. (1973). They fell into two categories. 5 patients had a raised plasma viscosity (PV) and in each case a definite pathology was found to account for this, superimposed on hypermobile joints. The remaining 16 had a normal PV and this group was thought to represent the late natural history of hypermobility. 5 of these (aged 32 to 54 years) had no evidence of osteoarthrosis but the remaining 11 (aged 34 to 80 years) had widespread radiological osteoarthrosis. Synovial histology was obtained at arthroscopy in 6 of these patients and 4 (aged 60 to 75) had chondrocalcinosis. This previously undescribed finding may be the end result of hypermobile joints. Hypermobile patients with joint deformity (lax connective tissue), widespread synovial thickening (traumatic), and hot joint effusions (chondrocalcinosis) may mimic rheumatoid arthritis. They must be distinguished from patients who develop rheumatoid arthritis in hypermobile joints. Images PMID:686857

  9. What role do plain radiographs have in assessing the skeletally immature acromioclavicular joint?

    PubMed

    Lee, Seung Yeol; Kwon, Soon-Sun; Chung, Chin Youb; Lee, Kyoung Min; Park, Moon Seok

    2014-01-01

    Because of incomplete ossification of the coracoid process and acromion, acromioclavicular joint configuration in the skeletally immature patient differs from that of adults. Although comparison to radiographic standards for this joint is critical in the evaluation of acromioclavicular joint injuries, these standards are not well defined for children or adolescents. We therefore sought to determine (1) the reliability of numerous radiographic measurements of the skeletally immature acromioclavicular joint, including the vertical and shortest coracoclavicular interval, and the acromioclavicular joint offset; (2) the timing of ossification of the acromion and coracoid in males and females; and (3) the differences in the values of these radiographic measurements based on age and sex. This study was based on a total of 485 subjects, 8 to 18 years old, who underwent conventional AP view radiographs of both shoulders. The 485 subjects were included to assess normal configuration around the acromioclavicular joint and 466 of these subjects were evaluated for comparison between both sides. The vertical and shortest coracoclavicular interval, coracoclavicular clavicle width ratio, acromioclavicular joint offset, and difference of the coracoclavicular interval of both sides were measured. A reliability test was conducted before obtaining the main measurements. The relationship of measurements with sex, age, and stage of ossification was evaluated. The vertical and shortest coracoclavicular interval showed excellent reliability (intraclass correlation coefficient ([ICC], 0.918 and 0.934). The acromioclavicular joint offset showed low reliability (ICC, 0.543). The ossification centers of the acromion and the coracoid processes appeared and fused earlier in females than in males. The vertical coracoclavicular interval, which was not affected by partial ossification of the coracoid process, was less than 11 mm in the 90% quantile of total subjects in males and 10 mm in the 90

  10. Evaluation of pipe-type cable joint restraint systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Silver, D.A.; Seman, G.W.

    1990-03-01

    the purpose of this project was to evaluate two systems for restraining the movement of 345kV high-pressure oil-filled (HPOF) cable joints during load cycling. Problems with joints and adjacent cables due to thermomechanical bending (TMB) experienced by the Consolidated Edison Company of New York and Public Service Electric Gas Company of New Jersey are reviewed. Some approaches to reducing or preventing TMB induced damage to HPOF pipe type cable joints are discussed. The design and operation of a special test apparatus for simulating TMB effects under laboratory conditions is described. One of the two joint restraint systems evaluated under thismore » project was developed by PSE G and employed wedging devices, which could be retrofitted into existing installations, that limited the longitudinal movement of the joints during load cycling. The other system developed by Pirelli Cable Corporation applied the restraining force to the cylindrical portion of the hand applied joint insulation by means of support spiders and steel rods attached to the reducer faces. The test results show that the PSE G restraint system can effectively limit joint longitudinal movement while causing a minimal amount of mechanical disturbance to the joint stress cones. The test results obtained with the PCC system are inconclusive and indicate that further refinement and testing are required to demonstrate the effectiveness of this promising joint restraint system.« less

  11. Current Options and Emerging Biomaterials for Periprosthetic Joint Infection.

    PubMed

    Levack, Ashley E; Cyphert, Erika L; Bostrom, Mathias P; Hernandez, Christopher J; von Recum, Horst A; Carli, Alberto V

    2018-04-30

    Infection in the setting of total joint arthroplasty, referred to as periprosthetic joint infection (PJI), is a devastating complication requiring prolonged and costly treatment. The unique environment around an artificial joint and ability of surrounding tissues to sequester bacteria collectively make prevention, diagnosis, and treatment of this condition challenging. In light of the unique pathogenesis of PJI, this review explores the limitations of contemporary treatments and discusses novel treatment options. Recent advancements in local antibiotic delivery platforms for preventing and treating PJI include titanium nanotube arrays, synthetic polymers, resorbable hydrogels, and cyclodextrin-based drug delivery options. In particular, cyclodextrins have facilitated great advancements in other clinical disorders and have demonstrated early promise as a future option in the arena of PJI. Novel treatment modalities for PJI optimize the implant surfaces to prevent bacterial biofilm formation or provide prolonged intra-articular antibiotic dosing to eradicate bacteria.

  12. Effect of Risk Acceptance for Bundled Care Payments on Clinical Outcomes in a High-Volume Total Joint Arthroplasty Practice After Implementation of a Standardized Clinical Pathway.

    PubMed

    Kee, James R; Edwards, Paul K; Barnes, Charles L

    2017-08-01

    The Bundled Payments for Care Improvement (BPCI) initiative and the Arkansas Payment Improvement (API) initiative seek to incentivize reduced costs and improved outcomes compared with the previous fee-for-service model. Before participation, our practice initiated a standardized clinical pathway (CP) to reduce length of stay (LOS), readmissions, and discharge to postacute care facilities. This practice implemented a standardized CP focused on patient education, managing patient expectations, and maximizing cost outcomes. We retrospectively reviewed all primary total joint arthroplasty patients during the initial 2-year "at risk" period for both BPCI and API and determined discharge disposition, LOS, and readmission rate. During the "at risk" period, the average LOS decreased in our total joint arthroplasty patients and our patients discharged home >94%. Patients within the BPCI group had a decreased discharge to home and decreased readmission rates after total hip arthroplasty, but also tended to be older than both API and nonbundled payment patients. While participating in the BPCI and API, continued use of a standardized CP in a high-performing, high-volume total joint practice resulted in maintenance of a low-average LOS. In addition, BPCI patients had similar outcomes after total knee arthroplasty, but had decreased rates of discharge to home and readmission after total hip arthroplasty. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Joint Commission

    MedlinePlus

    ... Progress, June 2016 issue, explores The Joint Commission’s internal Robust Process Improvement ® program. Read the ... cry for improving our services. It has provided a pulpit from which we structure quality and safety activities and get buy-in from ...

  14. Functionally Graded Adhesives for Composite Joints

    NASA Technical Reports Server (NTRS)

    Stapleton, Scott E.; Waas, Anthony M.; Arnold, Steven M.

    2012-01-01

    Adhesives with functionally graded material properties are being considered for use in adhesively bonded joints to reduce the peel stress concentrations located near adherend discontinuities. Several practical concerns impede the actual use of such adhesives. These include increased manufacturing complications, alterations to the grading due to adhesive flow during manufacturing, and whether changing the loading conditions significantly impact the effectiveness of the grading. An analytical study is conducted to address these three concerns. An enhanced joint finite element, which uses an analytical formulation to obtain exact shape functions, is used to model the joint. Furthermore, proof of concept testing is conducted to show the potential advantages of functionally graded adhesives. In this study, grading is achieved by strategically placing glass beads within the adhesive layer at different densities along the joint.

  15. Thumb carpometacarpal joint resurfacing with autologous ear cartilage.

    PubMed

    Nickell, William B

    2014-05-01

    A study was designed to ascertain the long-term effectiveness of using autologous full-thickness ear cartilage to resurface the arthritic face of the trapezium, leaving the body of the trapezium intact. The value of injection of the involved carpometacarpal (CMC) joint with local anesthetic in predicting improvement from the surgery was also studied. An operation was used to enter the CMC joint of the thumb between the thenar muscles and the abductor tendon. The articular surface of the trapezium was resected and resurfaced with full-thickness ear cartilage from the patient's ear. Patients were selected based on constant, unremitting pain. All patients also had x-ray evidence of severe arthritis at the CMC joint of the thumb. Both thumbs were evaluated for pain, range of motion, key and palmar pinch, and grip strength before the surgery and followed up for a minimum of 30 months to be included in the study. Fifty-nine patients had ear cartilage arthroplasty from 1997 to 2007 by the same surgeon with a total of 67 operations (8 patients, all women, had both thumbs operated). Forty-nine of these patients, 4 men and 45 women (53 hands), were available for follow-up and constitute the study group. Eight procedures were done on the left hand, and 45, on the right. There were no ear complications and no cartilage extrusions. All patients had improved range of motion and greatly decreased pain. Strength was equaled or exceeded the unoperated thumb. Preoperative joint injection was a good predictor of postoperative pain relief. All patients were pleased with the result and said that they would have the surgery again. Thumb CMC joint arthroplasty with autologous ear cartilage and preservation of the body of the trapezium is an effective alternative to existing procedures.There is no morbidity to the ear, and predictable long-term improvement in thumb pain and strength can be obtained. Injection of the CMC joint before surgery with local anesthetic is a reliable predictor of

  16. [Fetal bone and joint disorders].

    PubMed

    Jakobovits, Akos

    2008-12-21

    The article discusses the physiology and pathology of fetal bone and joint development and functions. The bones provide static support for the body. The skull and the bones of spinal column encase the central and part of the peripheral nervous system. The ribs and the sternum shield the heart and the lungs, while the bones of the pelvis protect the intraabdominal organs. Pathological changes of these bony structures may impair the functions of the respective systems or internal organs. Movements of the bones are brought about by muscles. The deriving motions are facilitated by joints. Bony anomalies of the extremities limit their effective functions. Apart from skeletal and joint abnormalities, akinesia may also be caused by neurological, muscular and skin diseases that secondarily affect the functions of bones and joints. Such pathological changes may lead to various degrees of physical disability and even to death. Some of the mentioned anomalies are recognizable in utero by ultrasound. The diagnosis may serve as medical indication for abortion in those instances when the identified abnormality is incompatible with independent life.

  17. The mechanoreceptors of the costo-vertebral joints

    PubMed Central

    Godwin-Austen, R. B.

    1969-01-01

    1. Unitary recording in the thoracic dorsal roots of mechanoreceptor discharges from the costo-vertebral joints was carried out in the cat and rabbit. Criteria for the identification of costo-vertebral joint mechanoreceptors were established. 2. The majority of rib joint mechanoreceptors are slowly adapting and fifty-three such receptors were studied. Five rapidly adapting receptors were also identified. 3. The responses of these receptors have been correlated with rib position and movement. The slowly adapting receptors gave a monotonic response to different rib positions. 72% showed an increase of discharge rate with displacements towards expiratory rib positions. 4. In response to manually imposed rib movements slowly adapting joint mechanoreceptors gave a dynamic response which was directly related to the velocity of the movement and adapted within 2 sec. The movements of breathing produced a corresponding alteration of the discharge frequency of the slowly adapting receptors. 5. Slowly adapting receptors were localized to the capsule of the costo-transverse joint by probing. They responded to increased intra-articular pressure with an increase of discharge rate and were silenced by intra-articular lignocaine, 0·4%. 6. Rapidly adapting joint mechanoreceptors responded to rib movement with a brief burst of discharges. 7. The rib joint mechanoreceptors signal rib joint position, and the direction and velocity of rib movement. It is suggested that these afferent discharges provide the basis for the perception of respiratory movements of the chest. The significance of these receptors to the `sense of effort' resulting from a resistance to breathing is discussed. PMID:5789947

  18. PAIN FROM INTRA-ARTICULAR NGF OR JOINT INJURY IN THE RAT REQUIRES CONTRIBUTIONS FROM PEPTIDERGIC JOINT AFFERENTS

    PubMed Central

    Kras, Jeffrey V.; Weisshaar, Christine L.; Pall, Parul S.; Winkelstein, Beth A.

    2015-01-01

    Non-physiological stretch of the cervical facet joint’s capsular ligament induces persistent behavioral hypersensitivity and spinal neuronal hyperexcitability via an intra-articular NGF-dependent mechanism. Although that ligament is innervated by nociceptors, it is unknown if a subpopulation is exclusively responsible for the behavioral and spinal neuronal responses to intra-articular NGF and/or facet joint injury. This study ablated joint afferents using the neurotoxin saporin targeted to neurons involved in either peptidergic ([Sar9,Met(O2)11]-substance P-saporin (SSP-Sap)) or non-peptidergic (isolectin B4-saporin (IB4-Sap)) signaling to investigate the contributions of those neuronal populations to facet-mediated pain. SSP-Sap, but not IB4-Sap, injected into the bilateral C6/C7 facet joints 14 days prior to an intra-articular NGF injection prevents NGF-induced mechanical and thermal hypersensitivity in the forepaws. Similarly, only SSP-Sap prevents the increase in mechanical forepaw stimulation-induced firing of spinal neurons after intra-articular NGF. In addition, intra-articular SSP-Sap prevents both behavioral hypersensitivity and upregulation of NGF in the dorsal root ganglion after a facet joint distraction that normally induces pain. These findings collectively suggest that disruption of peptidergic signaling within the joint may be a potential treatment for facet pain, as well as other painful joint conditions associated with elevated NGF, such as osteoarthritis. PMID:26240991

  19. The serpentine end-matched joint: evaluating strength and stability

    Treesearch

    Charles J. Gatchell; Curtis C. Peters

    1981-01-01

    The Serpentine end-matched (Sem) joint is a precisely machined butt joint with a sine wave shape. The joint is not readily visible to the eye and performs well in panels made of sugar maple, red oak, black walnut, and black cherry. The Sem joint is unaffected by changes in equilibrium moisture content from 6 to 12 to 18 to 6 percent. Panels containing Sem joints have...

  20. Reconstructive surgery for patellofemoral joint incongruency.

    PubMed

    Neumann, M V; Stalder, M; Schuster, A J

    2016-03-01

    A retrospective analysis of a heterogeneous patient cohort was performed to determine the outcome and eligibility of a combined trochleaplasty and soft tissue-balancing technique for repair of patellofemoral joint disorders. A strict surgical treatment algorithm including trochleaplasty and reconstruction of the medial patellofemoral ligament and vastus medialis oblique muscle was implemented to restore the patellofemoral joint. A heterogeneous patient cohort including 46 consecutively treated symptomatic knees was reviewed. The median follow-up period was 4.7 years (range 24-109 months). No patellar redislocation occurred post-operatively, and the median Kujala score improved from 62 (9-96) to 88 (47-100) points (p < 0.001) at follow-up. Radiological signs of trochlear dysplasia were corrected, and both patellar height and trochlear depth were significantly restored after surgery. In total, 16% of affected patients with pre-existing patellofemoral degenerative changes showed progression of osteoarthrosis according to the Kellgren and Lawrence classification. The surgical combination of trochleaplasty and reconstruction of the medial patellofemoral ligament and vastus medialis oblique muscle offers excellent clinical and radiological results. The overall results of the present study showed significant improvement of the Kujala score in patients with Dejour grades C and D dysplasia. These results outline the clinical relevance of trochleaplasty with additional soft tissue balancing as an effective joint-preserving method with satisfying results in patients with pre-existing degenerative changes. IV.

  1. Cross-Shear Implementation in Sliding-Distance-Coupled Finite Element Analysis of Wear in Metal-on-Polyethylene Total Joint Arthroplasty: Intervertebral Total Disc Replacement as an Illustrative Application

    PubMed Central

    Goreham-Voss, Curtis M.; Hyde, Philip J.; Hall, Richard M.; Fisher, John; Brown, Thomas D.

    2010-01-01

    Computational simulations of wear of orthopaedic total joint replacement implants have proven to valuably complement laboratory physical simulators, for pre-clinical estimation of abrasive/adhesive wear propensity. This class of numerical formulations has primarily involved implementation of the Archard/Lancaster relationship, with local wear computed as the product of (finite element) contact stress, sliding speed, and a bearing-couple-dependent wear factor. The present study introduces an augmentation, whereby the influence of interface cross-shearing motion transverse to the prevailing molecular orientation of the polyethylene articular surface is taken into account in assigning the instantaneous local wear factor. The formulation augment is implemented within a widely-utilized commercial finite element software environment (ABAQUS). Using a contemporary metal-on-polyethylene total disc replacement (ProDisc-L) as an illustrative implant, physically validated computational results are presented to document the role of cross-shearing effects in alternative laboratory consensus testing protocols. Going forward, this formulation permits systematically accounting for cross-shear effects in parametric computational wear studies of metal-on-polyethylene joint replacements, heretofore a substantial limitation of such analyses. PMID:20399432

  2. Hydrothermal corrosion of silicon carbide joints without radiation

    DOE PAGES

    Koyanagi, Takaaki; Katoh, Yutai; Terrani, Kurt A.; ...

    2016-09-28

    In this paper, hydrothermal corrosion of four types of the silicon carbide (SiC) to SiC plate joints were investigated under pressurized water reactor and boiling water reactor relevant chemical conditions without irradiation. The joints were formed by metal diffusion bonding using molybdenum or titanium interlayer, reaction sintering using Ti—Si—C system, and SiC nanopowder sintering. Most of the joints withstood the corrosion tests for five weeks. The recession of the SiC substrates was limited. Based on the recession of the bonding layers, it was concluded that all the joints except for the molybdenum diffusion bond are promising under the reducing environmentsmore » without radiation. Finally, the SiC nanopowder sintered joint was the most corrosion tolerant under the oxidizing environment among the four joints.« less

  3. Clinical characteristics, microbiology, and outcomes of prosthetic joint infection in Taiwan.

    PubMed

    Tsai, Jen-Chih; Sheng, Wang-Huei; Lo, Wan-Yu; Jiang, Ching-Chuan; Chang, Shan-Chwen

    2015-04-01

    Prosthetic joint infection (PJI) after total knee or hip replacement is a devastating complication associated with substantial morbidity and economic cost. The incidence of prosthetic joint infection is increasing as the use of mechanical joint replacement increases. The treatment approach to prosthetic joint infection is based on different clinical situations such as a patient's comorbidities, epidemic microbiology data, and surgical procedures. The aim of our study was to understand clinical characteristics of prosthetic joint infection, the microbiology of the prosthetic joint infection, and the outcomes of different treatment strategies during 2006-2011. We retrospectively collected cases of prosthetic joint infection in the National Taiwan University Hospital between January 1, 2006 and December 31, 2011. The patients' characteristics, microbiology, outcomes, and factors associated with treatment success were recorded. One hundred and forty-four patients were identified as having PJI. Of these, 92 patients were entered into per-protocol analysis. Staphylococcus aureus was the most common causative organism (29.9%), followed by coagulase-negative Staphylococci (16.7%), and Enterococci (9.7%). The overall treatment success rate was 50%. Patients who received a two-stage revision had a better outcome, compared to patients who underwent other types of surgeries (70% vs. 32.7%, respectively; p < 0.001). In multivariate analysis, the two-stage revision was significantly associated with treatment success (odds ratio = 3.923, 95% confidence interval = 1.53-10.04). Our study demonstrates that Staphylococcus aureus was the most common causative organisms in PJI. Performing two-stage revisions was significantly associated with a better outcome. Copyright © 2013. Published by Elsevier B.V.

  4. Kinematically aligned TKA can align knee joint line to horizontal.

    PubMed

    Ji, Hyung-Min; Han, Jun; Jin, Dong San; Seo, Hyunseok; Won, Ye-Yeon

    2016-08-01

    The joint line of the native knee is horizontal to the floor and perpendicular to the vertical weight-bearing axis of the patient in a bipedal stance. The purposes of this study were as follows: (1) to find out the distribution of the native joint line in a population of normal patients with normal knees; (2) to compare the native joint line orientation between patients receiving conventional mechanically aligned total knee arthroplasty (TKA), navigated mechanically aligned TKA, and kinematically aligned TKA; and (3) to determine which of the three TKA methods aligns the postoperative knee joint perpendicular to the weight-bearing axis of the limb in bipedal stance. To determine the joint line orientation of a native knee, 50 full-length standing hip-to-ankle digital radiographs were obtained in 50 young, healthy individuals. The angle between knee joint line and the line parallel to the floor was measured and defined as joint line orientation angle (JLOA). JLOA was also measured prior to and after conventional mechanically aligned TKA (65 knees), mechanically aligned TKA using imageless navigation (65 knees), and kinematically aligned TKA (65 knees). The proportion of the knees similar to the native joint line was calculated for each group. The mean JLOA in healthy individuals was parallel to the floor (0.2° ± 1.1°). The pre-operative JLOA of all treatment groups slanted down to the lateral side. Postoperative JLOA slanted down to the lateral side in conventional mechanically aligned TKA (-3.3° ± 2.2°) and in navigation mechanically aligned TKA (-2.6° ± 1.8°), while it was horizontal to the floor in kinematically aligned TKA (0.6° ± 1.7°). Only 6.9 % of the conventional mechanically aligned TKA and 16.9 % of the navigation mechanically aligned TKA were within one SD of the mean JLOA of the native knee, while the proportion was significantly higher (50.8 %) in kinematically aligned TKA. The portion was statistically greater in mechanically

  5. Maximum voluntary joint torque as a function of joint angle and angular velocity: model development and application to the lower limb.

    PubMed

    Anderson, Dennis E; Madigan, Michael L; Nussbaum, Maury A

    2007-01-01

    Measurements of human strength can be important during analyses of physical activities. Such measurements have often taken the form of the maximum voluntary torque at a single joint angle and angular velocity. However, the available strength varies substantially with joint position and velocity. When examining dynamic activities, strength measurements should account for these variations. A model is presented of maximum voluntary joint torque as a function of joint angle and angular velocity. The model is based on well-known physiological relationships between muscle force and length and between muscle force and velocity and was tested by fitting it to maximum voluntary joint torque data from six different exertions in the lower limb. Isometric, concentric and eccentric maximum voluntary contractions were collected during hip extension, hip flexion, knee extension, knee flexion, ankle plantar flexion and dorsiflexion. Model parameters are reported for each of these exertion directions by gender and age group. This model provides an efficient method by which strength variations with joint angle and angular velocity may be incorporated into comparisons between joint torques calculated by inverse dynamics and the maximum available joint torques.

  6. Failure Assessment Diagram for Titanium Brazed Joints

    NASA Technical Reports Server (NTRS)

    Flom, Yury; Jones, Justin S.; Powell, Mollie M.; Puckett, David F.

    2011-01-01

    The interaction equation was used to predict failure in Ti-4V-6Al joints brazed with Al 1100 filler metal. The joints used in this study were geometrically similar to the joints in the brazed beryllium metering structure considered for the ATLAS telescope. This study confirmed that the interaction equation R(sub sigma) + R(sub Tau) = 1, where R(sub sigma) and R(sub Tau)are normal and shear stress ratios, can be used as conservative lower bound estimate of the failure criterion in ATLAS brazed joints as well as for construction of the Failure Assessment Diagram (FAD).

  7. Resident accuracy of joint line palpation using ultrasound verification.

    PubMed

    Rho, Monica E; Chu, Samuel K; Yang, Aaron; Hameed, Farah; Lin, Cindy Yuchin; Hurh, Peter J

    2014-10-01

    To determine the accuracy of knee and acromioclavicular (AC) joint line palpation in Physical Medicine and Rehabilitation (PM&R) residents using ultrasound (US) verification. Cohort study. PM&R residency program at an academic institution. Twenty-four PM&R residents participating in a musculoskeletal US course (7 PGY-2, 8 PGY-3, and 9 PGY4 residents). Twenty-four PM&R residents participating in an US course were asked to palpate the AC joint and lateral joint line of the knee in a female and male model before the start of the course. Once the presumed joint line was localized, the residents were asked to tape an 18-gauge, 1.5-inch, blunt-tip needle parallel to the joint line on the overlying skin. The accuracy of needle placement over the joint line was verified using US. US verification of correct needle placement over the joint line. Overall AC joint palpation accuracy was 16.7%, and knee lateral joint line palpation accuracy was 58.3%. Based on the resident level of education, using a value of P < .05, there were no statistically significant differences in the accuracy of joint line palpation. Residents in this study demonstrate poor accuracy of AC joint and lateral knee joint line identification by palpation, using US as the criterion standard for verification. There were no statistically significant differences in the accuracy rates of joint line palpation based on resident level of education. US may be a useful tool to use to advance the current methods of teaching the physical examination in medical education. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  8. Fungal Periprosthetic Joint Infection in Total Knee Arthroplasty: A Systematic Review

    PubMed Central

    Jakobs, Oliver; Schoof, Benjamin; Klatte, Till Orla; Schmidl, Stefan; Fensky, Florian; Guenther, Daniel; Frommelt, Lars; Gehrke, Thorsten; Gebauer, Matthias

    2015-01-01

    Fungal periprosthetic joint infection (PJI) is a rare but devastating complication following total knee arthroplasty (TKA). A standardized procedure regarding an accurate treatment of this serious complication of knee arthroplasty is lacking. In this systematic review, we collected data from 36 studies with a total of 45 reported cases of a TKA complicated by a fungal PJI. Subsequently, an analysis focusing on diagnostic, medicaments and surgical procedures in the pre-, intra- and postoperative period was performed. Candida spp. accounts for about 80% (36 out of 45 cases) of fungal PJIs and is therefore the most frequently reported pathogen. A systemic antifungal therapy was administered in all but one patient whereas a local antifungal therapy, e.g. the use of an impregnated spacer, is of inferior relevance. Resection arthroplasty with delayed re-implantation (two-stage revision) was the surgical treatment of choice. However, in 50% of all reported cases the surgical therapy was heterogeneous. The outcome under a combined therapy was moderate with recurrent fungal PJI in 11 patients and subsequent bacterial PJI as a main complication in 5 patients. In summary, this systematic review integrates data from up to date 45 reported cases of a fungal PJI of a TKA. On the basis of the current literature strategies for the treatment of this devastating complication after TKA are discussed. PMID:25874061

  9. Management of chronic unstable acromioclavicular joint injuries.

    PubMed

    Cisneros, Luis Natera; Reiriz, Juan Sarasquete

    2017-12-01

    The acromioclavicular joint represents the link between the clavicle and the scapula, which is responsible for the synchronized dynamic of the shoulder girdle. Chronic acromioclavicular joint instability involves changes in the orientation of the scapula, which provokes cinematic alterations that might result in chronic pain. Several surgical strategies for the management of patients with chronic and symptomatic acromioclavicular joint instability have been described. The range of possibilities includes anatomical and non-anatomical techniques, open and arthroscopy-assisted procedures, and biological and synthetic grafts. Surgical management of chronic acromioclavicular joint instability should involve the reconstruction of the torn ligaments because it is accepted that from three weeks after the injury, these structures may lack healing potential. Here, we provide a review of the literature regarding the management of chronic acromioclavicular joint instability. Expert opinion, Level V.

  10. Pressure relief and other joint rehabilitation techniques : appendices

    DOT National Transportation Integrated Search

    1987-02-01

    Appendices of a study of four major concrete pavement joint rehabilitation techniques has been conducted, including: pressure relief joints, full-depth repairs, partial-depth repairs and joint resealing. The products of this research include the foll...

  11. Improving joint pain and function in osteoarthritis.

    PubMed

    Owens, Claire; Conaghan, Philip G

    2016-12-01

    Osteoarthritis has become a major chronic pain condition. It affects more than 10% of adults and accounts for almost 10% of health service resources. The impact of osteoarthritis is amplified by underuse of effective muscle strengthening exercises and a focus on often less effective and poorly tolerated analgesic therapies. Although traditionally considered to be primarily a disease of cartilage, there is now ample evidence that typical clinical osteoarthritis involves multiple tissue pathologies. Increased BMI is associated with a higher incidence of knee osteoarthritis. Anatomical abnormalities such as valgus alignment or previous joint trauma including meniscectomy, anterior cruciate ligament rupture and fracture through the joint are also associated with increased incidence of osteoarthritis. Pain is the main presenting symptom. However, we still have a poor understanding of the causes of pain in osteoarthritis. In patients aged 45 or over the diagnosis should be made clinically without investigations if the patient has activity-related joint pain in addition to early morning joint stiffness lasting less than 30 minutes. Muscle strengthening and aerobic exercise have been shown to improve joint pain and function. Weight loss not only improves joint pain and function but has a myriad of other health benefits, reducing the incidence of lifestyle associated diseases such as cardiovascular disease and type 2 diabetes, and mechanical stress on the joints.

  12. [Determination of joint contact area using MRI].

    PubMed

    Yoshida, Hidenori; Kobayashi, Koichi; Sakamoto, Makoto; Tanabe, Yuji

    2009-10-20

    Elevated contact stress on the articular joints has been hypothesized to contribute to articular cartilage wear and joint pain. However, given the limitations of using contact stress and areas from human cadaver specimens to estimate articular joint stress, there is need for an in vivo method to obtain such data. Magnetic resonance imaging (MRI) has been shown to be a valid method of quantifying the human joint contact area, indicating the potential for in vivo assessment. The purpose of this study was to describe a method of quantifying the tibiofemoral joint contact area using MRI. The validity of this technique was established in porcine cadaver specimens by comparing the contact area obtained from MRI with the contact area obtained using pressure-sensitive film (PSF). In particular, we assessed the actual condition of contact by using the ratio of signal intensity of MR images of cartilage surfaces. Two fresh porcine cadaver knees were used. A custom loading apparatus was designed to apply a compressive load to the tibiofemoral joint. We measured the contact area by using MRI and PSF methods. When the ratio of signal intensity of the cartilage surface was 0.9, the error of the contact area between the MR image and PSF was about 6%. These results suggest that this MRI method may be a valuable tool in quantifying joint contact area in vivo.

  13. Gulf Coast Joint Venture - Contact Us

    Science.gov Websites

    Contact us Gulf Coast Joint Venture Wetland and Aquatic Research Center 700 Cajundome Blvd. Lafayette, LA Coast Joint Venture - 700 Cajundome Blvd. - Lafayette, LA 70506 Phone: 337-266-8801 Fax: 337-266-8800

  14. Advances in Proximal Interphalangeal Joint Arthroplasty: Biomechanics and Biomaterials.

    PubMed

    Zhu, Andy F; Rahgozar, Paymon; Chung, Kevin C

    2018-05-01

    Proximal interphalangeal (PIP) joint arthritis is a debilitating condition. The complexity of the joint makes management particularly challenging. Treatment of PIP arthritis requires an understanding of the biomechanics of the joint. PIP joint arthroplasty is one treatment option that has evolved over time. Advances in biomaterials have improved and expanded arthroplasty design. This article reviews biomechanics and arthroplasty design of the PIP joint. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Experimental Investigation of the Influence of Joint Geometric Configurations on the Mechanical Properties of Intermittent Jointed Rock Models Under Cyclic Uniaxial Compression

    NASA Astrophysics Data System (ADS)

    Liu, Yi; Dai, Feng; Fan, Pengxian; Xu, Nuwen; Dong, Lu

    2017-06-01

    Intermittent joints in rock mass are quite sensitive to cyclic loading conditions. Understanding the fatigue mechanical properties of jointed rocks is beneficial for rational design and stability analysis of rock engineering projects. This study experimentally investigated the influences of joint geometry (i.e., dip angle, persistency, density and spacing) on the fatigue mechanism of synthetic jointed rock models. Our results revealed that the stress-strain curve of jointed rock under cyclic loadings is dominated by its curve under monotonic uniaxial loadings; the terminal strain in fatigue curve is equal to the post-peak strain corresponding to the maximum cyclic stress in the monotonic stress-strain curve. The four joint geometrical parameters studied significantly affect the fatigue properties of jointed rocks, including the irreversible strains, the fatigue deformation modulus, the energy evolution, the damage variable and the crack coalescence patterns. The higher the values of the geometrical parameters, the lower the elastic energy stores in this jointed rock, the higher the fatigue damage accumulates in the first few cycles, and the lower the fatigue life. The elastic energy has certain storage limitation, at which the fatigue failure occurs. Two basic micro-cracks, i.e., tensile wing crack and shear crack, are observed in cyclic loading and unloading tests, which are controlled principally by joint dip angle and persistency. In general, shear cracks only occur in the jointed rock with higher dip angle or higher persistency, and the jointed rock is characterized by lower fatigue strength, larger damage variable and lower fatigue life.

  16. Adaptive Postural Control for Joint Immobilization during Multitask Performance

    PubMed Central

    Hsu, Wei-Li

    2014-01-01

    Motor abundance is an essential feature of adaptive control. The range of joint combinations enabled by motor abundance provides the body with the necessary freedom to adopt different positions, configurations, and movements that allow for exploratory postural behavior. This study investigated the adaptation of postural control to joint immobilization during multi-task performance. Twelve healthy volunteers (6 males and 6 females; 21–29 yr) without any known neurological deficits, musculoskeletal conditions, or balance disorders participated in this study. The participants executed a targeting task, alone or combined with a ball-balancing task, while standing with free or restricted joint motions. The effects of joint configuration variability on center of mass (COM) stability were examined using uncontrolled manifold (UCM) analysis. The UCM method separates joint variability into two components: the first is consistent with the use of motor abundance, which does not affect COM position (VUCM); the second leads to COM position variability (VORT). The analysis showed that joints were coordinated such that their variability had a minimal effect on COM position. However, the component of joint variability that reflects the use of motor abundance to stabilize COM (VUCM) was significant decreased when the participants performed the combined task with immobilized joints. The component of joint variability that leads to COM variability (VORT) tended to increase with a reduction in joint degrees of freedom. The results suggested that joint immobilization increases the difficulty of stabilizing COM when multiple tasks are performed simultaneously. These findings are important for developing rehabilitation approaches for patients with limited joint movements. PMID:25329477

  17. Joint Online Thesis and Research System (JOTARS)

    DTIC Science & Technology

    2006-09-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS Approved for public release; distribution is unlimited JOINT ONLINE ...September 2006 3. REPORT TYPE AND DATES COVERED Master’s Thesis 4. TITLE AND SUBTITLE: Joint Online Thesis and Research System (JOTARS) 6. AUTHOR...prototype website is the Joint Online Thesis and Research System (JOTARS). The specific functional objectives of JOTARS are to establish standard

  18. [Treatment of bacterial infection in the interphalangeal joints of the hand].

    PubMed

    Vorderwinkler, K-P; Mühldorfer, M; Pillukat, T; van Schoonhoven, J

    2011-07-01

    Radical debridement of joint infection, prevention of further infection-related tissue destruction. Septic arthritis of interphalangeal joints in the thumb and fingers. Extensive soft tissue defects. Severe impairment of blood circulation, finger gangrene. Noncompliance for immobilization or for treatment with external fixator. Arthrotomy and irrigation with isotonic solution. Radical tissue debridement. Joint preservation possible only in the absence of infection-related macroscopic cartilage damage. Otherwise, resection of the articular surfaces and secondary arthrodesis. Insertion of antibiotic-coated devices. Temporary immobilization with external fixator. Inpatient postoperative treatment with 5-day intravenous administration of a second-generation cephalosporine (e.g., Cefuroxim®) followed by 7-10 days oral application. Adaptation of antibiotics according to antibiogram results. In joint-preserving procedures, radiographs and fixator removal after 4 weeks, active joint mobilization. If joint surfaces were resected, removal of fixator after 6 weeks; arthrodesis under 3-day intravenous broad-band antibiotic prophylaxis. Splint immobilization until consolidation (6-8 weeks). In 10 of 40 patients, the infected joint could be preserved. All infections healed. After an average duration of therapy of 6 (3-11) weeks, 4 individuals were free of complaints, and 6 patients had minor symptoms. Overall range of motion in the affected finger was reduced by 25-50° in 5 patients. All patients could return to work after 6.6 (4-11) weeks. A total of 30 patients were treated with joint resection and external fixator. After 5.6 (4-8) weeks, arthrodesis was performed, leading to consolidation in 29 patients. One patient underwent amputation after 4 months due to delayed gangrene. Treatment duration was 15.7 (7-25) weeks. Eight patients reported no complaints, 14 suffered mild symptoms, 5 had moderate, and 3 had severe symptoms in daily life. In 15 cases, range

  19. Hybrid FSWeld-bonded joint fatigue behaviour

    NASA Astrophysics Data System (ADS)

    Lertora, Enrico; Mandolfino, Chiara; Gambaro, Carla; Pizzorni, Marco

    2018-05-01

    Aluminium alloys, widely used in aeronautics, are increasingly involved in the automotive industry due to the good relationship between mechanical strength and specific weight. The lightening of the structures is the first objective, which allows the decreasing in the weight in motion. The use of aluminium alloys has also seen the introduction of the Friction Stir Welding (FSW) technique for the production of structural overlapping joints. FSW allows us to weld overlap joints free from defects, but with the presence of a structural notch further aggravated by the presence of a "hook" defect near the edge of the weld. Furthermore, FSW presents a weld penetration area connected to the tool geometry and penetration. The experimental activity will be focused on the combination of two different joining techniques, which can synergistically improve the final joint resistance. In particular, the welding and bonding process most commonly known as weld-bonding is defined as a hybrid process, as it combines two different junction processes. In this paper we analyse FSWelded AA6082 aluminium alloy overlapped joint with the aim of quantitatively evaluating the improvement provided by the presence of an epoxy adhesive between the plates. After optimising the weld-bonding process, the mechanical behaviour of welded joints will be analysed by static and dynamic tests. The presence of the adhesive should limit the negative effect of the structural notch inevitable in a FSW overlapped joint.

  20. Language Competence and Joint Attention in Mother-Toddler Dyads.

    ERIC Educational Resources Information Center

    Saxon, Terrill F.; Reilly, John T.

    1998-01-01

    Investigated the relationship between language competence, joint attention, and interaction between mothers and toddlers that fosters joint attention. Found no correlation between joint attention and concurrent language, yet joint attention was related to toddler age when correlated with language. Suggested that nonostensive settings need further…

  1. 49 CFR 178.345-4 - Joints.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Containers for Motor Vehicle Transportation § 178.345-4 Joints. (a) All joints between the cargo tank shell... accessible for inspection. [Amdt. 178-89, 54 FR 25022, June 12, 1989, as amended by Amdt. 178-118, 61 FR...

  2. 49 CFR 178.345-4 - Joints.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Containers for Motor Vehicle Transportation § 178.345-4 Joints. (a) All joints between the cargo tank shell... accessible for inspection. [Amdt. 178-89, 54 FR 25022, June 12, 1989, as amended by Amdt. 178-118, 61 FR...

  3. 49 CFR 178.345-4 - Joints.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Containers for Motor Vehicle Transportation § 178.345-4 Joints. (a) All joints between the cargo tank shell... accessible for inspection. [Amdt. 178-89, 54 FR 25022, June 12, 1989, as amended by Amdt. 178-118, 61 FR...

  4. 49 CFR 178.345-4 - Joints.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Containers for Motor Vehicle Transportation § 178.345-4 Joints. (a) All joints between the cargo tank shell... accessible for inspection. [Amdt. 178-89, 54 FR 25022, June 12, 1989, as amended by Amdt. 178-118, 61 FR...

  5. 49 CFR 178.345-4 - Joints.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Containers for Motor Vehicle Transportation § 178.345-4 Joints. (a) All joints between the cargo tank shell... accessible for inspection. [Amdt. 178-89, 54 FR 25022, June 12, 1989, as amended by Amdt. 178-118, 61 FR...

  6. Prosthetic elbow joint

    NASA Technical Reports Server (NTRS)

    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.

  7. Application of Bionic Design to FRP T-Joints

    NASA Astrophysics Data System (ADS)

    Luo, Guang-Min; Kuo, Chia-Hung

    2017-09-01

    We applied the concepts of bionics to enhance the mechanical strength of fiberglass reinforced plastic T-joints. The failure modes of the designed arthrosis-like and gum-like joints were determined using three-point bending tests and numerical simulations and compared with those of normal T-joints bonded using structural adhesives. In the simulation, we used cohesive elements to simulate the adhesive interface of the structural adhesive. The experimental and simulation results show that the arthrosis-like joint can effectively delay the failure progress and enhance the bonding strength of T-joints, thus confirming that an appropriate bionic design can effectively control the bonding properties of structural adhesives.

  8. Flaw Tolerance in Lap Shear Brazed Joints. Part 1

    NASA Technical Reports Server (NTRS)

    Flom, Yury; Wang, Li-Qin

    2003-01-01

    Furnace brazing is a joining process used in the aerospace and other industries to produce strong permanent and hermetic structural joints. As in any joining process, brazed joints have various imperfections and defects. At the present time, our understanding of the influence of the internal defects on the strength of the brazed joints is not adequate. The goal of this 3-part investigation is to better understand the properties and failure mechanisms of the brazed joints containing defects. This study focuses on the behavior of the brazed lap shear joints because of their importance in manufacturing aerospace structures. In Part 1, an average shear strength capability and failure modes of the single lap joints are explored. Stainless steel specimens brazed with pure silver are tested in accordance with the AWS C3.2 standard. Comparison of the failure loads and the ultimate shear strength with the Finite Element Analysis (FEA) of the same specimens as a function of the overlap widths shows excellent correlation between the experimental and calculated values for the defect-free lap joints. A damage zone criterion is shown to work quite well in understanding the failure of the braze joints. In Part 2, the findings of the Part 1 will be verified on the larger test specimens. Also, various flaws will be introduced in the test specimens to simulate lack of braze coverage in the lap joints. Mechanical testing and FEA will be performed on these joints to verify that behavior of the flawed ductile lap joints is similar to joints with a reduced braze area. Finally, in Part 3, the results obtained in Parts 1 and 2 will be applied to the actual brazed structure to evaluate the load-carrying capability of a structural lap joint containing discontinuities. In addition, a simplified engineering procedure will be offered for the laboratory testing of the lap shear specimens.

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

    PubMed

    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 < .001). Non-VA care was completely eliminated for patients undergoing total hip and knee replacement at the Richard L. Roudebush Veterans Affairs Medical Center, producing an estimated return on investment of $1 million annually when compared with baseline cost and volumes. In addition, the volume of total joint replacements at this center increased during the data collection period. The success of the Joint Replacement Program demonstrates that VA-TAMMCS is an effective tool for Lean and Six Sigma process improvement initiatives in a surgical practice, producing a 36% sustained reduction in

  10. Study of sealing practices for rigid pavement joints.

    DOT National Transportation Integrated Search

    1971-01-01

    The joint sealing materials and the rigid pavement joint sealing practices employed by Virginia and other highway agencies were studied. The studies showed that Virginia's sealant and joint designs were in need of updating and that higher quality pou...

  11. High temperature ceramic/metal joint structure

    DOEpatents

    Boyd, Gary L.

    1991-01-01

    A high temperature turbine engine includes a hybrid ceramic/metallic rotor member having ceramic/metal joint structure. The disclosed joint is able to endure higher temperatures than previously possible, and aids in controlling heat transfer in the rotor member.

  12. Comparison of arthrodesis, resurfacing hemiarthroplasty, and total joint replacement in the treatment of advanced hallux rigidus.

    PubMed

    Erdil, Mehmet; Elmadağ, Nuh Mehmet; Polat, Gökhan; Tunçer, Nejat; Bilsel, Kerem; Uçan, Vahdet; Erkoçak, Omer Faruk; Sen, Cengiz

    2013-01-01

    The purpose of the present study was to compare the functional results of arthrodesis, resurfacing hemiarthroplasty, and total joint replacement in hallux rigidus. The data from patients treated from 2006 to 2010 for advanced stage hallux rigidus were retrospectively reviewed. A total of 38 patients who had at least 2 years (range 24 to 66 months, mean 31.1) of follow-up were included in the present study. Of the 38 patients, 12 were included in the total joint replacement group (group A), 14 in the resurfacing hemiarthroplasty group (group B), and 12 in the arthrodesis group (group C). At the last follow-up visit, the functional outcomes were evaluated using the American Orthopaedic Foot and Ankle Society-Hallux Metatarsophalangeal Interphalangeal (AOFAS-HMI) scale, visual analog scale (VAS), and metatarsophalangeal range of motion. Significant improvements were seen in the AOFAS-HMI score, with a decrease in the VAS score in all 3 groups. According to the AOFAS-HMI score, no significant difference was found between groups A and B. However, in group C, the AOFAS-HMI scores were significantly lower than in the other groups owing to the lack of motion. According to the final VAS scores, no significant difference was found between groups A and B; however, the VAS score had decreased significantly more in group C than in the other groups. No major complications occurred in any of the 3 groups. After 2 years of follow-up, all the groups had good functional outcomes. Although arthrodesis is still the most reliable procedure, implant arthroplasty is also a good alternative for advanced stage hallux rigidus. Copyright © 2013 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  13. The effects of load carriage on joint work at different running velocities.

    PubMed

    Liew, Bernard X W; Morris, Susan; Netto, Kevin

    2016-10-03

    Running with load carriage has become increasingly prevalent in sport, as well as many field-based occupations. However, the "sources" of mechanical work during load carriage running are not yet completely understood. The purpose of this study was to determine the influence of load magnitudes on the mechanical joint work during running, across different velocities. Thirty-one participants performed overground running at three load magnitudes (0%, 10%, 20% body weight), and at three velocities (3, 4, 5m/s). Three dimensional motion capture was performed, with synchronised force plate data captured. Inverse dynamics was used to quantify joint work in the stance phase of running. Joint work was normalized to a unit proportion of body weight and leg length (one dimensionless work unit=532.45J). Load significantly increased total joint work and total positive work and this effect was greater at faster velocities. Load carriage increased ankle positive work (β coefficient=rate of 6.95×10 -4 unit work per 1% BW carried), and knee positive (β=1.12×10 -3 unit) and negative work (β=-2.47×10 -4 unit), and hip negative work (β=-7.79×10 -4 unit). Load carriage reduced hip positive work and this effect was smaller at faster velocities. Inter-joint redistribution did not contribute significantly to altered mechanical work within the spectrum of load and velocity investigated. Hence, the ankle joint contributed to the greatest extent in work production, whilst that of the knee contributed to the greatest extent to work absorption when running with load. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. The potential influence of regionalization strategies on delivery of care for elective total joint arthroplasty.

    PubMed

    Dy, Christopher J; Marx, Robert G; Ghomrawi, Hassan M K; Pan, Ting Jung; Westrich, Geoffrey H; Lyman, Stephen

    2015-01-01

    Regionalization of total joint arthroplasty (TJA) to high volume hospitals (HVHs) may affect access to care and complication risk. Using administrative data, 2,560,314 patients who underwent primary total hip or knee arthroplasty from 1991 to 2006 were categorized by whether an HVH (>200 annual TJAs) was available locally. Associations among patient characteristics, hospital utilization, and in-hospital complications were estimated using regression modeling. The complication risk was higher (Odds Ratio 1.18 [95% CI: 1.16, 1.20]) if patients went to a local low volume hospital. Black and Medicaid patients were more likely to utilize the local low volume hospital than a local HVH. Utilizing a local HVH is associated with lower complication risks. However, patients from vulnerable groups were less likely to utilize these patterns. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. No difference in joint awareness after mobile- and fixed-bearing total knee arthroplasty: 3-year follow-up of a randomized controlled trial.

    PubMed

    Schotanus, M G M; Pilot, P; Vos, R; Kort, N P

    2017-12-01

    To compare the patients ability to forget the artificial knee joint in everyday life who were randomized to be operated for mobile- or fixed-bearing total knee arthroplasty (TKA). This single-center randomized controlled trial evaluated the 3-year follow-up of the cemented mobile- and fixed-bearing TKA from the same brand in a series of 41 patients. Clinical examination was during the pre-, 6-week, 6-month, 1-, 2- and 3-year follow-up containing multiple patient-reported outcome measures (PROMs) including the 12-item Forgotten Joint Score (FJS-12) at 3 years. Effect size was calculated for each PROM at 3-year follow-up to quantify the size of the difference between both bearings. At 3-year follow-up, general linear mixed model analysis showed that there were no significant or clinically relevant differences between the two groups for all outcome measures. Calculated effect sizes were small (<0.3) for all the PROMs except for the FJS-12; these were moderate (0.5). The results of this study demonstrate that joint awareness was slightly lower in patients operated with the MB TKA with comparable improved clinical outcome and PROMs at 3-year follow-up. Measuring joint awareness with the FJS-12 is useful and provides more stringent information at 3-year follow-up compared to other PROMs and should be the PROM of choice at each follow-up after TKA. Level I, randomized controlled trial.

  16. Pharmacologic Hemostatic Agents in Total Joint Arthroplasty-A Cost-Effectiveness Analysis.

    PubMed

    Ramkumar, Dipak B; Ramkumar, Niveditta; Tapp, Stephanie J; Moschetti, Wayne E

    2018-03-03

    Total knee and hip arthroplasties can be associated with substantial blood loss, affecting morbidity and even mortality. Two pharmacological antifibrinolytics, ε-aminocaproic acid (EACA) and tranexamic acid (TXA) have been used to minimize perioperative blood loss, but both have associated morbidity. Given the added cost of these medications and the risks associated with then, a cost-effectiveness analysis was undertaken to ascertain the best strategy. A cost-effectiveness model was constructed using the payoffs of cost (in United States dollars) and effectiveness (quality-adjusted life expectancy, in days). The medical literature was used to ascertain various complications, their probabilities, utility values, and direct medical costs associated with various health states. A time horizon of 10 years and a willingness to pay threshold of $100,000 was used. The total cost and effectiveness (quality-adjusted life expectancy, in days) was $459.77, $951.22, and $1174.87 and 3411.19, 3248.02, and 3342.69 for TXA, no pharmacologic hemostatic agent, and EACA, respectively. Because TXA is less expensive and more effective than the competing alternatives, it was the favored strategy. One-way sensitivity analyses for probability of transfusion and myocardial infarction for all 3 strategies revealed that TXA remains the dominant strategy across all clinically plausible values. TXA, when compared with no pharmacologic hemostatic agent and with EACA, is the most cost-effective strategy to minimize intraoperative blood loss in hip and knee total joint arthroplasties. These findings are robust to sensitivity analyses using clinically plausible probabilities. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Biomechanics of unilateral and bilateral sacroiliac joint stabilization: laboratory investigation.

    PubMed

    Lindsey, Derek P; Parrish, Robin; Gundanna, Mukund; Leasure, Jeremi; Yerby, Scott A; Kondrashov, Dimitriy

    2018-03-01

    OBJECTIVE Bilateral symptoms have been reported in 8%-35% of patients with sacroiliac (SI) joint dysfunction. Stabilization of a single SI joint may significantly alter the stresses on the contralateral SI joint. If the contralateral SI joint stresses are significantly increased, degeneration may occur; alternatively, if the stresses are significantly reduced, bilateral stabilization may be unnecessary for patients with bilateral symptoms. The biomechanical effects of 1) unilateral stabilization on the contralateral SI joint and 2) bilateral stabilization on both SI joints are currently unknown. The objectives of this study were to characterize bilateral SI joint range of motion (ROM) and evaluate and compare the biomechanical effects of unilateral and bilateral implant placement for SI joint fusion. METHODS A lumbopelvic model (L5-pelvis) was used to test the ROM of both SI joints in 8 cadavers. A single-leg stance setup was used to load the lumbar spine and measure the ROM of each SI joint in flexion-extension, lateral bending, and axial rotation. Both joints were tested 1) while intact, 2) after unilateral stabilization, and 3) after bilateral stabilization. Stabilization consisted of lateral transiliac placement of 3 triangular titanium plasma-sprayed (TPS) implants. RESULTS Intact testing showed that during single-leg stance the contralateral SI joint had less ROM in flexion-extension (27%), lateral bending (32%), and axial rotation (69%) than the loaded joint. Unilateral stabilization resulted in significant reduction of flexion-extension ROM (46%) on the treated side; no significant ROM changes were observed for the nontreated side. Bilateral stabilization resulted in significant reduction of flexion-extension ROM of the primary (45%) and secondary (75%) SI joints. CONCLUSIONS This study demonstrated that during single-leg loading the ROMs for the stance (loaded) and swing (unloaded) SI joints are significantly different. Unilateral stabilization for SI

  18. Towards understanding knee joint laxity: errors in non-invasive assessment of joint rotation can be corrected.

    PubMed

    Moewis, P; Boeth, H; Heller, M O; Yntema, C; Jung, T; Doyscher, R; Ehrig, R M; Zhong, Y; Taylor, W R

    2014-07-01

    The in vivo quantification of rotational laxity of the knee joint is of importance for monitoring changes in joint stability or the outcome of therapies. While invasive assessments have been used to study rotational laxity, non-invasive methods are attractive particularly for assessing young cohorts. This study aimed to determine the conditions under which tibio-femoral rotational laxity can be assessed reliably and accurately in a non-invasive manner. The reliability and error of non-invasive examinations of rotational joint laxity were determined by comparing the artefact associated with surface mounted markers against simultaneous measurements using fluoroscopy in five knees including healthy and ACL deficient joints. The knees were examined at 0°, 30°, 60° and 90° flexion using a device that allows manual axial rotation of the joint. With a mean RMS error of 9.6°, the largest inaccuracy using non-invasive assessment was present at 0° knee flexion, whereas at 90° knee flexion, a smaller RMS error of 5.7° was found. A Bland and Altman assessment indicated that a proportional bias exists between the non-invasive and fluoroscopic approaches, with limits of agreement that exceeded 20°. Correction using average linear regression functions resulted in a reduction of the RMS error to below 1° and limits of agreement to less than ±1° across all knees and flexion angles. Given the excellent reliability and the fact that a correction of the surface mounted marker based rotation values can be achieved, non-invasive evaluation of tibio-femoral rotation could offer opportunities for simplified devices for use in clinical settings in cases where invasive assessments are not justified. Although surface mounted marker based measurements tend to overestimate joint rotation, and therefore joint laxity, our results indicate that it is possible to correct for this error. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

  19. Robotic joint experiments under ultravacuum

    NASA Technical Reports Server (NTRS)

    Borrien, A.; Petitjean, L.

    1988-01-01

    First, various aspects of a robotic joint development program, including gearbox technology, electromechanical components, lubrication, and test results, are discussed. Secondly, a test prototype of the joint allowing simulation of robotic arm dynamic effects is presented. This prototype is tested under vacuum with different types of motors and sensors to characterize the functional parameters: angular position error, mechanical backlash, gearbox efficiency, and lifetime.

  20. Joint Actions of Developmental Toxicants.

    DTIC Science & Technology

    1991-06-01

    antagonistic response may have been the result of poorer absorption of hydroxyurea by the severly malformed embryos, as isoniazid had a much greater...chain carboxylic acids showed concentration additive joint actions for induction of malformation . Combinations of DNA synthesis inhibitors showed...response additive to antagonistic joint actions at malformation -inducing con- centrations. Since each compound inhibits a different enzyme in the process of