Joint Replacement (joint + replacement)

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Joint Replacement

  • hip joint replacement
  • total joint replacement

  • Terms modified by Joint Replacement

  • joint replacement surgery

  • Selected Abstracts


    INCIDENCE AND OUTCOMES OF KNEE AND HIP JOINT REPLACEMENT IN VETERANS AND CIVILIANS

    ANZ JOURNAL OF SURGERY, Issue 5 2006
    Vanessa Wells
    Background: This article describes the incidence of total knee and hip replacement, and compares post-surgery health status outcomes in veterans and civilians. Methods: The numbers of male veterans and civilians who had a knee and/or a hip replacement in South Australia (1994,2002) were obtained. Standardized morbidity ratios, and odds ratios for age group by veteran/civilian interactions, were calculated. Presurgery and 1-year post-surgery Medical Outcomes Short Form (36) Health Survey, Knee Society and Harris hip scores were completed. Independent samples t -tests were used to compare presurgery scores. ancova models were used to determine any differences between veterans and civilians post-surgery. Results: For veterans, standardized morbidity ratios were 0.987 and 0.715 for knee and hip replacements, respectively (P < 0.0001). Veterans' odds ratios for knee and hip replacements were significantly lower in the 65- to 74-year age group (P < 0.001), similar in the 75- to 84-year and above 85-year age groups for hip replacement, but significantly higher in the above 85-year age group for knee replacement (P < 0.001). Presurgery, veterans reported significantly lower scores (P < 0.003) for knee function. After knee replacement, veterans reported significantly lower Medical Outcomes Short Form (36) Health Survey scores for bodily pain, physical functioning, role , physical, role , emotional, social functioning and physical component summary (P < 0.033). Significantly lower physical functioning, role , physical and physical component summary scores (P < 0.02) were reported by veterans post-surgery for hip replacement. Conclusion: Veterans are delaying joint replacement. Presurgical knee function is worse in veterans. Post-surgery, the veterans are worse off in a number of health status outcomes. [source]


    FACTORS AFFECTING IMPLANT RETENTION IN INFECTED JOINT REPLACEMENTS

    ANZ JOURNAL OF SURGERY, Issue 10 2007
    Jean-Claude Theis
    Background: There is no standard treatment for infected joint replacements. The options available are varied, and treatment choices may pose problems in relation to both efficacy and cost-effectiveness. Methods: A retrospective review of 73 patient records identified in our departmental audit database as infected joint replacements treated at Dunedin Hospital between 1990 and 2000 was carried out. The findings were analysed in terms of outcome of primary treatment, final outcome including prosthesis retention and bacteriology. Results: Of the 73 patients (50 hips and 20 knees), the majority (69%) were managed by primary surgical debridement followed by intravenous antibiotics but about one-third (34%) lost their implants because of infection. Retention of implants was higher in acute infections (85,100%) as opposed to late infections (20,50%). The microbiological analysis showed that Staphylococcus and Streptococcus caused the majority (76%) of infections. Conclusion: In our series, a patient with an infected joint replacement had an approximately similar 30% chance of retaining the original prosthesis, undergoing a successful revision and having no implants in situ at the end of treatment. [source]


    The safety and outcome of joint replacement surgery in liver transplant recipients

    LIVER TRANSPLANTATION, Issue 4 2003
    Josh Levitsky
    A small group of patients may require total hip arthroplasty, total knee arthroplasty, or other joint replacement surgery after OLT for osteoporotic fractures, osteonecrosis, and osteoarthritis. Although arthroplasty is safe in the general population, its safety in liver transplant recipients is unclear. The aim of the study was to determine the safety and outcome of joint replacement surgery in our liver transplant recipients. A retrospective analysis was performed on all liver transplant recipients who had total joint arthroplasty at a single teaching institution between 1986 and 2002. Data regarding major intraoperative and postoperative complications was obtained from the medical charts and a hospital-based computer system. Of over 1,200 liver transplant recipients, we identified 7 patients who underwent 12 total arthroplasties (8 knee, 3 hip, 1 ankle). Joint replacements were performed electively for osteonecrosis (5 of 12) and osteoarthritis (5 of 12), whereas two hip arthroplasties were performed emergently for fractures. All patients with osteonecrosis or hip fracture had been treated with prolonged corticosteroids. There were no deaths or major complications in the intraoperative and postoperative periods. On long-term follow-up, no patients have had pain, dislocation, or infection in the postsurgical joint. No joint revision surgery has been required. In conclusion, a small number of stable liver transplant recipients at our institution underwent joint replacement surgery without major short-term or long-term complications. Our study suggests that joint replacement surgery may be safely and successfully performed in this population, although larger, randomized, prospective trials are needed to confirm our findings. [source]


    I PREVENT Bacterial Resistance.

    DERMATOLOGIC SURGERY, Issue 10 2009
    An Update on the Use of Antibiotics in Dermatologic Surgery
    BACKGROUND AND OBJECTIVES Prophylaxis may be given to prevent a surgical wound infection, infective endocarditis (IE), or infection of a prosthetic joint, but its use before cutaneous surgery is controversial. Our aim was to review the current literature and provide a mnemonic to assist providers in appropriately prescribing prophylactic antibiotics. METHODS AND MATERIALS We reviewed the current literature, including the new guidelines provided by the American Heart Association (AHA). RESULTS The new AHA guidelines recommend prophylaxis for patients with high risk of an adverse outcome from IE instead of high risk of developing IE. The American Academy of Orthopedic Surgeons and the American Dental Association also provide guidelines. Given the paucity of conclusive studies, prophylaxis against a surgical wound infection is based more on clinical judgment. CONCLUSION The mnemonic we propose, "I PREVENT," represents: Immunosuppressed patients; patients with a Prosthetic valve; some patients with a joint Replacement; a history of infective Endocarditis; a Valvulopathy in cardiac transplant recipients; Endocrine disorders such as uncontrolled diabetes mellitus; Neonatal disorders including unrepaired cyanotic heart disorders (CHDs), repaired CHD with prosthetic material, or repaired CHD with residual defects; and the Tetrad of antibiotics: amoxicillin, cephalexin, clindamycin, and ciprofloxacin. [source]


    Idiopathic post-traumatic dermatitis at the site of recent joint replacement

    CONTACT DERMATITIS, Issue 1 2008
    S. M. Bewsher
    Idiopathic dermatitis over the site of previous trauma is a recognized but infrequently reported phenomenon that provides a diagnostic dilemma. Careful investigation is needed in order to exclude other rare and/or treatable causes. [source]


    Health economics of treating haemophilia A with inhibitors

    HAEMOPHILIA, Issue 2005
    C. KNIGHT
    Summary., Haemophilia is a rare, inherited blood disorder in which blood clotting is impaired such that patients suffer from excessive internal and external bleeding. At present there is no cure for haemophilia A and patients require expensive, life-long treatment involving clotting factor replacement therapy. Treatment costs are perceived to be higher for patients who have developed inhibitory antibodies to factor VIII, the standard therapy for haemophilia A. However, initial cost analyses suggest that clotting factor therapy with alternative haemostatic agents, such as recombinant activated factor VII or activated prothrombin complex concentrate, is no more expensive for the majority of haemophilia A patients with inhibitors than for those without inhibitors. With the availability of effective alternative haemostatic agents, orthopaedic surgery for haemophilia A patients with inhibitors is now a clinical option, and initial cost analyses suggest this may be a cost-effective treatment strategy for patients with inhibitors whose quality of life (QoL) is severely impaired by joint arthropathy. In an era of finite healthcare resourcing it is important to determine whether new treatments justify higher unit costs compared with standard therapies and whether such higher costs are justified from an individual perspective in terms of improved QoL, and from a societal perspective in terms of improved productivity and reduced overall healthcare costs. This paper examines current data on the health economics of treating haemophilia A patients with inhibitors, focusing on the overall costs of clotting factor replacement therapy and the cost consequences of joint replacement. [source]


    A bird can't fly on one wing: patient views on waiting for hip and knee replacement surgery

    HEALTH EXPECTATIONS, Issue 2 2007
    Barbara L. Conner-Spady PhD
    Abstract Objectives, To obtain patients' perspectives on acceptable waiting times for hip or knee replacement surgery. Methods, A questionnaire with both open- and close-ended items was mailed to 432 consecutive patients who had hip or knee replacement surgery 3,12 months previously in Saskatchewan, Canada. A content analysis was used to analyse the text data from the open-ended questions. Results, The sample of 303 (response rate 70%) was 59% female with a mean age of 70 years (SD 11). The median waiting time from the decision date to surgery was 17 weeks. Individuals who rated their waiting time very acceptable (48%) had a median waiting time of 13 weeks compared with a median waiting time of 22 weeks for those who rated it unacceptable (23%). The two most common determinants of acceptability were patient expectations and pain and its impact on patient quality of life. The median maximum acceptable waiting time was 13 weeks and median ideal waiting time, 8.6 weeks. Seventy-nine per cent felt that those in greater need (higher severity) should go before them on the waiting list. Patient ratings of maximum acceptable waiting time were based on: pain and loss of mobility, time needed to prepare for surgery, and severity at the time of seeing the surgeon. In consideration of changing their surgeon to one with a shorter waiting list, 68% would not. Conclusions, Patient views on waiting times are not only related to quality of life issues, but also to prior expectations and notions of fairness and priority. Understanding patient views on waiting for surgery has implications for better management of waiting times and experiences for joint replacement. [source]


    Changes in Regional Variation of Medicare Home Health Care Utilization and Service Mix for Patients Undergoing Major Orthopedic Procedures in Response to Changes in Reimbursement Policy

    HEALTH SERVICES RESEARCH, Issue 4 2009
    John D. FitzGerald
    Background. Significant variation in regional utilization of home health (HH) services has been documented. Under Medicare's Home Health Interim and Prospective Payment Systems, reimbursement policies designed to curb expenditure growth and reduce regional variation were instituted. Objective. To examine the impact of Medicare reimbursement policy on regional variation in HH care utilization and type of HH services delivered. Research Design. We postulated that the reimbursement changes would reduce regional variation in HH services and that HH agencies would respond by reducing less skilled HH aide visits disproportionately compared with physical therapy or nursing visits. An interrupted time-series analysis was conducted to examine regional variation in the month-to-month probability of HH selection, and the number of and type of visits among HH users. Subjects. A 100 percent sample of all Medicare recipients undergoing either elective joint replacement (1.6 million hospital discharges) or surgical management of hip fracture (1.2 million hospital discharges) between January 1996 and December 2001 was selected. Results. Before the reimbursement changes, there was great variability in the probability of HH selection and the number of HH visits provided across regions. In response to the reimbursement changes, though there was little change in the variation of probability of HH utilization, there were marked reductions in the number and variation of HH visits, with greatest reductions in regions with highest baseline utilization. HH aide visits were the source of the baseline variation and accounted for the majority of the reductions in utilization after implementation. Conclusions. The HH interim and prospective payment policies were effective in reducing regional variation in HH utilization. [source]


    Amyloidosis: a rheumatological perspective on diagnosis, further investigation and treatment

    INTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 1 2008
    S. K. L. LAM
    Abstract In this Grand Round, we present a 58-year-old man with a presumptive diagnosis of rheumatoid arthritis (RA) who was being managed by a plastic surgery unit for a dorsal swelling of his right hand. While awaiting surgery for this lesion, he sustained a pathological fracture of his left neck of femur. This necessitated a total hip joint replacement and pathology revealed amyloidosis. Excision of the hand swelling also revealed amyloidosis as the cause. We discuss the ways in which amyloidosis can mimic musculoskeletal disease as well as the importance and some potential pitfalls of further investigation and management once the diagnosis of amyloidosis has been made. [source]


    Effect of long-term natural aging on the thermal, mechanical, and viscoelastic behavior of biomedical grade of ultra high molecular weight polyethylene

    JOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2010
    H. Fouad
    Abstract In the total joint prostheses, Ultra High Molecular Weight Polyethylene (UHMWPE) may undergo an oxidative degradation in the long term. The overall properties of UHMWPE are expected to be altered due to the oxidative degradation. The goal of this study is to investigate the effects of natural aging up to 6 years in air on the thermal, mechanical, and viscoelastic properties of UHMWPE that was used in total joint replacement. The changes in UHMWPE properties due to aging are determined using Differential Scanning Calorimetry (DSC), uniaxial tensile tests, and Dynamic Mechanical Analysis (DMA). The DSC results show that the lamellar thickness and degree of crystallinity of UHMWPE specimens increase by 38% and 12% due to aging. A small shoulder region in the DSC thermograms is remarked for aged specimens, which is an indication of formation of new crystalline forms within their amorphous region. The tensile properties of aged and nonaged UHMWPE specimens show a significant decrease in the elastic modulus, yield, fracture stresses, and strain at break due to aging. The DM testing results indicate that the storage modulus and creep resistance of UHMWPE specimens decrease significantly due to aging. Also, it is remarked that the , relaxation peak for aged UHMWPE specimens occurs at lower temperature compared to nonaged ones. The significant reduction in the strength and creep resistance of UHMWPE specimens due to aging would affect the long-term clinical performance of the total joint replacement and should be taken into consideration during artificial joint design. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source]


    Ion release in patients with metal-on-metal hip bearings in total joint replacement: A comparison with metal-on-polyethylene bearings

    JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 5 2002
    L. Savarino
    Abstract Polyethylene (PE) wear has been shown to be a problem in long-term joint replacement using metal-on-PE bearing. The use of metallic heads articulating with metallic cups could solve this problem: success will be enhanced if wear and corrosion of the articulating surfaces are maintained at a low level. New models with metal-on-metal bearing have been proposed, to be used mainly for young subjects: such coupling seems to have a reduced release, but it is unclear yet if the medium-term corrosion rate is really negligible or, on the contrary, it is significantly higher than in the metal-on-PE bearing. Aim of our study was the comparison of ion release in the serum of two groups of patients who had the same type of stable cementless prosthesis, but different bearing: twenty-six patients with metal-on-metal (Group A) and fifteen patients with metal-on-PE bearing (Group B) were examined. The follow-up was 14-38 months for group A and 18-34 months for group B. The serum concentration of chromium (Cr), cobalt (Co) and molybdenum (Mo) was measured. Twenty-two patients before surgery were used for comparison (Group C). The reference values were obtained from a population of twenty-two healthy subjects (Group D). Our findings indicate that metal-on-metal bearings produce a significantly higher systemic release of cobalt and chromium (ng/ml) when compared with levels found in metal-on-PE, pre-surgery and reference groups. Such a high release should induce to improve the bearing materials or, at least, to study the biologic fate of metal ions and consequently their long-term effects. In such a way a risk-to-benefit ratio for the patient could be established. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res (Appl Biomater) 63: 467,474, 2002 [source]


    Bilateral Femoral Head Osteonecrosis After Septic Shock and Multiorgan Failure,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 3 2004
    Mark J Bolland
    Abstract A case of bilateral femoral head osteonecrosis after septic shock is presented. We suggest that the osteonecrosis was caused by ischemic insults to the proximal femora. The association between septic shock and osteonecrosis has not been previously reported. Introduction: Osteonecrosis is an uncommon disorder characterized by the in situ death of bone. A diverse range of conditions has been associated with osteonecrosis. We present a case of bilateral femoral head osteonecrosis that occurred after an episode of septic shock. Materials and Methods: A 66-year-old woman presented with a left-sided renal stone and a urinary tract infection. Her condition rapidly progressed to a life-threatening illness with septic shock complicated by multiorgan failure, which necessitated prolonged intensive care and inotropic support. She made a full recovery but 3 months later developed bilateral osteonecrosis of the femoral heads requiring bilateral total hip joint replacement. Results and Conclusions: We propose that the osteonecrosis was caused by ischemic insults to the femoral heads as a result of the widespread systemic ischemia that occurred during her initial illness. To our knowledge, septic shock has not been previously described as a cause of osteonecrosis. Clinicians should be aware of this association, particularly in patients presenting with bone pain after episodes of sepsis. [source]


    Different hip and knee priority score systems: are they good for the same thing?

    JOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 5 2010
    Antonio Escobar MD PhD
    Abstract Objective, The aim of the present study was to compare two priority tools used for joint replacement for patients on waiting lists, which use two different methods. Methods, Two prioritization tools developed and validated by different methodologies were used on the same cohort of patients. The first, an IRYSS hip and knee priority score (IHKPS) developed by RAND method, was applied while patients were on the waiting list. The other, a Catalonia hip,knee priority score (CHKPS) developed by conjoint analysis, was adapted and applied retrospectively. In addition, all patients fulfilled pre-intervention the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Correlation between them was studied by Pearson correlation coefficient (r). Agreement was analysed by means of intra-class correlation coefficient (ICC), Kendall coefficient and Cohern kappa. The relationship between IHKPS, CHKPS and baseline WOMAC scores by r coefficient was studied. Results, The sample consisted of 774 consecutive patients. Pearson correlation coefficient between IHKPS and CHKPS was 0.79. The agreement study showed that ICC was 0.74, Kendall coefficient 0.86 and kappa 0.66. Finally, correlation between CHKPS and baseline WOMAC ranged from 0.43 to 0.64. The results according to the relationship between IHKPS and WOMAC ranged from 0.50 to 0.74. Conclusions, Results support the hypothesis that if the final objective of the prioritization tools is to organize and sort patients on the waiting list, although they use different methodologies, the results are similar. [source]


    Does the organization of care processes affect outcomes in patients undergoing total joint replacement?

    JOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 1 2010
    Kris Vanhaecht RN MSc PhD
    Abstract Background, Surgeons realize that safe and efficient care processes for total joint replacement requires more than just well-performed operations. Orthopaedic teams are reorganizing care process to improve efficacy and shorten length of stay. Little is known on the impact of organizational changes on patient outcome. This paper studies the relation between the organization of care processes and patient outcomes in hip and knee. Clinical pathways are used as one of the methods to structure the care process. Although evidence is available on the effect of pathways in total joint replacement, their impact with the organization of the care process has not been studied previously. Methods, A cross-sectional multicentre study was performed on 39 care processes and 737 consecutive patients. Regression models were used to analyse the relation between the organization of the care process and risk-adjusted patient outcomes. The use of pathways and the organization of the care process, measured by the Care Process Self Evaluation Tool (CPSET), were measured at organizational level. Length of stay, pain, mobility and elapsed time to discharge were measured at patient level. Results, The use of pathways had a positive effect on four out of five subscales and the overall CPSET score. Using pathways decreased length of stay (P = 0.014), pain (P = 0.052) and elapsed time to discharge (P = 0.003). The CPSET subscale communication was related with three risk adjusted outcomes. Multivariate analysis demonstrated a significant effect by three different variables on the length of stay; (1) use of pathways; (2) coordination of care processes; and (3) communication with patients and family. Both the use of pathways and coordination of the care process were determinants for the elapsed time to discharge. A significant interaction effect was found between use of pathways and coordination of the care process. Conclusion, This large multicentre study revealed the relation between the use of pathways, organization of the care process and patient outcomes. This information is important for both clinicians and managers to understand and further improve the organization of orthopaedic care. Level of evidence, Level I prognostic study. [source]


    Waiting list management: priority criteria or first-in first-out?

    JOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 4 2009
    A case for total joint replacement
    Abstract Background, Total joint replacements are interventions with large waiting times from indication to the surgery management. These patients can be managed in two ways; first-in first-out or through a priority tool. The aim of this study was to compare real time on waiting list (TWL) with a priority criteria score, developed by our team, in patients awaiting joint replacement due to osteoarthritis. Methods, Consecutive patients placed on waiting list were eligible. Patients fulfilled a questionnaire which included items of our priority tool and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) specific questionnaire. Other priority items were extracted from the clinical history. The priority tool gives a score from 0 to 100 points, and three categories (urgent, preferent and ordinary). We studied the differences among categories and TWL by means of one-way analysis of variance. Correlational analysis was used to evaluate association among priority score and TWL and WOMAC baseline and gains at 6 months with priority score and TWL. Results, We have studied 684 patients. Women represented 62% of sample. The mean age was 70 years. There were not association between the categories of priority score and TWL (P = 0.12). The rho correlation coefficient between TWL and priority score was ,0.11. Among baseline WOMAC scores and priority score, the rho coefficients were 0.79, 0.7 and 0.52 with function, pain and stiffness dimensions, respectively. There were differences in the mean scores of WOMAC dimensions according to the three priority categories (P < 0.001) but no with TWL categories. Data of gains in both health-related quality of life dimensions at 6 months were similar, with differences according to priority categories but no regarding TWL. Conclusions, The results of the study support the necessity of implementing a prioritization system instead of the actual system if we want to manage the waiting list for joint replacement with clinical equity. [source]


    Pain, physical functioning and quality of life of individuals awaiting total joint replacement: a longitudinal study

    JOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 1 2008
    Gretl A. McHugh PhD MSc
    Abstract Objectives, To investigate if pain, physical function and the quality of life changed among adults with osteoarthritis while on the waiting list for hip or knee joint replacement. Methods, A longitudinal study of patients listed for primary hip or knee joint replacement. Participants were interviewed at baseline (n = 105) and followed up at 3 (n = 84), 6 (n = 47) and 9 months (n = 24), or until their joint replacement. Measurement tools used were a visual analogue scale (VAS), Western Ontario and McMaster's Universities (WOMAC) Osteoarthritis Index and the Medical Outcomes Study Short Form Health Survey (SF-36). Results, Baseline data indicated high levels of pain as measured by VAS [mean 7.0 (SD 2.2)] and WOMAC pain [mean 11.2 (SD 3.5)]. At baseline, the mean physical function measured by WOMAC was 40.3 (SD 12.1). At the 3-month follow-up, there was significant deterioration in VAS pain scores (0.6; 95% CI mean difference 0.3, 1.0); WOMAC pain scores (1.2; 95% CI mean difference 0.7, 1.8) and WOMAC physical function scores (4.8; 95% CI mean difference 2.8, 6.7) compared with baseline. Conclusion, The often long wait for joint replacement surgery and deterioration in pain and physical function has highlighted the need for active management by health professionals while patients are on the waiting list. [source]


    Hypoxia-like effect of Cobalt Chromium alloy micro particles on fibroblasts in vitro

    JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 10 2010
    Bernadette K. Madathil
    Abstract Periprosthetic osteolysis leading to asceptic loosening remains the primary cause of failure of joint replacement. Although many inflammatory cell types have been implicated, the exact pathomechanisms of asceptic loosening have not been delineated. In the present study we have adopted a proteomic approach to elucidate the initial signals that are expressed to particulate material, using an in vitro cell culture system. Human lung fibroblasts MRC-5 were cultured with Cobalt Chromium (CoCr ASTM F-75, 1,7,µm) particles. Cells were harvested after 72,h incubation and total cellular proteins extracted for downstream analysis via 2D Gel Electrophoresis and tandem mass spectrometry using MALDI-TOF-TOF-MS. Thirteen protein spots showed greater than twofold increase, following 72,h incubation of fibroblast with CoCr particles. Four of these proteins were identified by tandem mass spectrometry. These were Annexin II, Pyruvate kinase, Triose phosphate isomerase, and N-myc downstream regulated gene 1 protein. Cobalt is a hypoxia mimicking agent and N-myc downstream regulated gene 1 protein, Triose phosphate isomerase, Pyruvate kinase, and Annexin II are important hypoxia regulated gene products that are found to be over expressed in cellular oxidative stress response. Our data indicates that exposure of fibroblast to CoCr alloy induces the transition of these cells into a hypoxia like state and oxidative stress even in normoxic culture conditions. The study reflects the possibility of the presence of a hypoxic environment in the periprosthetic tissue surrounding metallic implants. Published by Wiley Periodicals, Inc. J Orthop Res 28:1360,1367, 2010 [source]


    Fixation of hydroxyapatite-coated revision implants is improved by the surgical technique of cracking the sclerotic bone rim

    JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2009
    Brian Elmengaard
    Abstract Revision joint replacement has poorer outcomes that have been associated with poorer mechanical fixation. We investigate a new bone-sparing surgical technique that locally cracks the sclerotic bone rim formed during aseptic loosening. We inserted 16 hydroxyapatite-coated implants bilaterally in the distal femur of eight dogs, using a controlled weight-bearing experimental model that replicates important features of a typical revision setting. At 8 weeks, a control revision procedure and a crack revision procedure were performed on contralateral implants. The crack procedure used a splined tool to perform a systematic local perforation of the sclerotic bone rim of the revision cavity. After 4 weeks, the hydroxyapatite-coated implants were evaluated for mechanical fixation by a push-out test and for tissue distribution by histomorphometry. The cracking revision procedure resulted in significantly improved mechanical fixation, significantly more bone ongrowth and bone volume in the gap, and reduced fibrous tissue compared to the control revision procedure. The study demonstrates that the sclerotic bone rim prevents bone ingrowth and promotes fixation by fibrous tissue. The effect of the cracking technique may be due to improved access to the vascular compartment of the bone. The cracking technique is a simple surgical method that potentially can improve the fixation of revision implants in sclerotic regions important for obtaining the fixation critical for overall implant stability. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 996,1001, 2009 [source]


    Cross-linked N-telopeptide of type I collagen (NTx) in urine as a predictor of periprosthetic osteolysis

    JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 7 2006
    Thord von Schewelov
    Abstract Periprosthetic osteolysis is often nonsymptomatic and hard to visualize by conventional radiography. Cross-linked N-telopeptide of type I collagen (NTx), a marker of osteoclast mediated bone resorption, has been suggested to evaluate local particulate-induced osteolysis in patients operated on with a total hip prosthesis. Urine specimens were sampled after hip joint replacement in 160 patients. NTx was analyzed by a commercially available ELISA kit. Osteolysis was identified in the acetabulum and confirmed at operation. Using analysis of covariance to correct for differences in age, gender, and time after operation, NTx (mean SD) was 36,±,12 BCE/nM creatinine in patients with osteolysis (n,=,33) and 27,±,13 BCE/nM creatinine in patients without osteolysis (n,=,127) (p,=,0.003). Eighteen hips of 38 (47%), demonstrating an annual wear of more than 0.2 mm and an NTx value above 29 BCE/nM creatinine, had been revised due to osteolysis. The osteolysis prevalence in this group was increased 10 times (CI 4-23, p,<,0.05). Indeed, NTx release and annual wear were both associated with increased prevalence of osteolysis, however, independently of each other. NTx seems a feasible marker of periprosthetic osteolysis. A preoperative baseline NTx level is likely needed for its use as a predictor of periprosthetic osteolysis in individual cases. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 24:1342,1348, 2006 [source]


    Polyethylene cross-linking by two different methods reduces acetabular liner wear in a hip joint wear simulator

    JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2003
    Darryl D. D'Lima
    Advances in cross-linking have led to the development of wear resistant ultrahigh molecular weight polyethylene for total joint replacement. This study compared wear reduction by two different cross-linking methods as measured in a hip wear simulator. One highly cross-linked polyethylene was treated with 7.5 Mrad gamma irradiation with post-irradiation annealing and a sterilization dose of 2.5 Mrad (10 Gamma), while the other used 9.5 Mrad warm irradiation with 10 MeV electron-beam (9.5 EB). Liners of the same design, made from nominally cross-linked (gamma sterilized) polyethylene were also tested. Gravimetric wear analysis was performed every 500,000 cycles for 5,000,000 cycles. After correcting for weight gain due to water absorption, the nominally cross-linked liners demonstrated mean wear rates of 15.7 (±1.7) and 12.5 (±1.0) mg/million cycles. Both highly cross-linked polyethylene liners demonstrated significantly less wear than their respective controls (with mean wear rates of 1.5 (±1.2) and ,1.4 (±1.5) mg/million cycles). The 9.5 EB liners gained weight presumably due to increased fluid absorption, in addition to that measured in loaded,soaked control implants. Any wear occurring was therefore assumed to have been more than offset by weight gain. Highly cross-linked polyethylene was significantly more wear resistant than non- or nominally cross-linked polyethylene. The differences in wear rates between the two highly cross-linked polyethylene designs (9.5 EB or 10 Gamma) are probably too small to be clinically significant. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source]


    Advances in paediatric rheumatology: Beyond NSAIDs and joint replacement

    JOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 4 2004
    JE Munro
    Over the previous three decades there have been a number of dramatic changes in our understanding of both the pathogenesis and epidemiology of the rheumatic diseases of childhood. Improvements in the classification of paediatric-onset arthritides and international collaboration in terms of multicentre research have led to the development of new therapeutic agents and better methods of outcome assessment for these chronic and often disabling conditions. Fortunately for children with paediatric rheumatic diseases treatment regimes are now available that provide excellent disease control for many and remission induction for some. Challenges include clearer definition of the genetics and pathogenesis of the diseases, delineation of reliable biological markers for diagnosis and monitoring of disease activity. The future should also herald early identification of those with a poorer prognosis, together with the design of more powerful, safer and cheaper remission-inducing agents, given to the right patients at the right time. [source]


    FACTORS AFFECTING IMPLANT RETENTION IN INFECTED JOINT REPLACEMENTS

    ANZ JOURNAL OF SURGERY, Issue 10 2007
    Jean-Claude Theis
    Background: There is no standard treatment for infected joint replacements. The options available are varied, and treatment choices may pose problems in relation to both efficacy and cost-effectiveness. Methods: A retrospective review of 73 patient records identified in our departmental audit database as infected joint replacements treated at Dunedin Hospital between 1990 and 2000 was carried out. The findings were analysed in terms of outcome of primary treatment, final outcome including prosthesis retention and bacteriology. Results: Of the 73 patients (50 hips and 20 knees), the majority (69%) were managed by primary surgical debridement followed by intravenous antibiotics but about one-third (34%) lost their implants because of infection. Retention of implants was higher in acute infections (85,100%) as opposed to late infections (20,50%). The microbiological analysis showed that Staphylococcus and Streptococcus caused the majority (76%) of infections. Conclusion: In our series, a patient with an infected joint replacement had an approximately similar 30% chance of retaining the original prosthesis, undergoing a successful revision and having no implants in situ at the end of treatment. [source]


    INCIDENCE AND OUTCOMES OF KNEE AND HIP JOINT REPLACEMENT IN VETERANS AND CIVILIANS

    ANZ JOURNAL OF SURGERY, Issue 5 2006
    Vanessa Wells
    Background: This article describes the incidence of total knee and hip replacement, and compares post-surgery health status outcomes in veterans and civilians. Methods: The numbers of male veterans and civilians who had a knee and/or a hip replacement in South Australia (1994,2002) were obtained. Standardized morbidity ratios, and odds ratios for age group by veteran/civilian interactions, were calculated. Presurgery and 1-year post-surgery Medical Outcomes Short Form (36) Health Survey, Knee Society and Harris hip scores were completed. Independent samples t -tests were used to compare presurgery scores. ancova models were used to determine any differences between veterans and civilians post-surgery. Results: For veterans, standardized morbidity ratios were 0.987 and 0.715 for knee and hip replacements, respectively (P < 0.0001). Veterans' odds ratios for knee and hip replacements were significantly lower in the 65- to 74-year age group (P < 0.001), similar in the 75- to 84-year and above 85-year age groups for hip replacement, but significantly higher in the above 85-year age group for knee replacement (P < 0.001). Presurgery, veterans reported significantly lower scores (P < 0.003) for knee function. After knee replacement, veterans reported significantly lower Medical Outcomes Short Form (36) Health Survey scores for bodily pain, physical functioning, role , physical, role , emotional, social functioning and physical component summary (P < 0.033). Significantly lower physical functioning, role , physical and physical component summary scores (P < 0.02) were reported by veterans post-surgery for hip replacement. Conclusion: Veterans are delaying joint replacement. Presurgical knee function is worse in veterans. Post-surgery, the veterans are worse off in a number of health status outcomes. [source]


    Bilateral knee joint replacement

    ANZ JOURNAL OF SURGERY, Issue 9 2005
    Peter Choong FRACS
    No abstract is available for this article. [source]


    Involvement of different risk factors in clinically severe large joint osteoarthritis according to the presence of hand interphalangeal nodes

    ARTHRITIS & RHEUMATISM, Issue 9 2010
    Ana M. Valdes
    Objective To quantify the differences in risk factors influencing total hip replacement (THR) and total knee replacement (TKR) based on the presence versus absence of multiple interphalangeal nodes in 2 or more rays of the fingers of each hand in patients with large joint osteoarthritis (OA). Methods A group of 3,800 patients with large joint OA who underwent total joint replacement (1,201 of whom had the nodal phenotype) and 1,906 control subjects from 2 case,control studies and a population-based cohort in the UK were studied. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated for the risk of total joint replacement in association with age, sex, body mass index (BMI), height, and prevalence of the T allele in the GDF5 rs143383 polymorphism. ORs for total joint replacement were compared between cases of nodal OA and cases of non-nodal OA and between patients who underwent TKR and those who underwent THR. Results Age, sex, and BMI had significantly higher ORs for an association with total joint replacement in nodal OA cases than in non-nodal OA cases. The GDF5 polymorphism was significantly associated with THR in cases of nodal OA, but not in cases of non-nodal OA, and increased height was a risk factor for THR in non-nodal OA cases only. Female sex was a protective risk factor for TKR in non-nodal OA cases (OR 0.60, 95% CI 0.52,0.70) but was predisposing for TKR in the nodal form of OA (OR 1.83, 95% CI 1.49,2.26). The nodal phenotype was associated with a significantly higher risk of undergoing both THR and TKR (OR 1.46, 95% CI 1.09,1.94) and also a significantly higher risk of bilateral TKR (OR 1.70, 95% CI 1.37,2.11), but, paradoxically, was associated with a lower risk of bilateral THR (OR 0.72, 95% CI 0.56,0.91). Conclusion Nodal and non-nodal forms of large joint OA have significantly different risk factors and outcomes, indicating a different etiology for the 2 forms of OA. With regard to the likelihood of undergoing THR, this appears to be, at least in part, genetically determined. [source]


    Vascular cell adhesion molecule 1 as a predictor of severe osteoarthritis of the hip and knee joints

    ARTHRITIS & RHEUMATISM, Issue 8 2009
    Georg Schett
    Objective Osteoarthritis (OA) is a leading cause of pain and physical disability in middle-aged and older individuals. We undertook this study to determine predictors of the development of severe OA, apart from age and overweight. Methods Joint replacement surgery due to severe hip or knee OA was recorded over a 15-year period in the prospective Bruneck cohort study. Demographic characteristics and lifestyle and biochemical variables, including the level of soluble vascular cell adhesion molecule 1 (VCAM-1), were assessed at the 1990 baseline visit and tested as predictors of joint replacement surgery. Results Between 1990 and 2005, hip or knee joint replacement due to OA was performed in 60 subjects. VCAM-1 level emerged as a highly significant predictor of the risk of joint replacement surgery. Intervention rates were 1.9, 4.2, and 10.1 per 1,000 person-years in the first, second, and third tertiles, of the VCAM-1 level, respectively. In multivariable logistic regression analysis, the adjusted relative risk of joint replacement surgery in the highest versus the lowest tertile group of VCAM-1 level was 3.9 (95% confidence interval 1.7,8.7) (P < 0.001). Findings were robust in various sensitivity analyses and were consistent in subgroups. Addition of the VCAM-1 level to a risk model already including age, sex, and body mass index resulted in significant gains in model discrimination (C statistic) and calibration and in more accurate risk classification of individual participants. Conclusion The level of soluble VCAM-1 emerged as a strong and independent predictor of the risk of hip and knee joint replacement due to severe OA. If our findings can be reproduced in other epidemiologic cohorts, they will assist in routine risk classification and will contribute to a better understanding of the etiology of OA. [source]


    Functional analysis of the osteoarthritis susceptibility,associated GDF5 regulatory polymorphism

    ARTHRITIS & RHEUMATISM, Issue 7 2009
    Rainer J. Egli
    Objective Single-nucleotide polymorphism (SNP) rs143383 (T to C) in the 5,-untranslated region (5,-UTR) of GDF5 has recently been reported to be associated with osteoarthritis (OA) susceptibility, with lower expression of the risk-associated T allele observed in vitro and in vivo. The in vivo studies were performed on cartilage tissue from OA patients. The present study was undertaken to expand the analysis of the effect of this SNP on GDF5 allelic expression to more joint tissue types, to investigate for cis and trans factors that interact with the SNP, and to examine novel cis -acting GDF5 regulatory polymorphisms. Methods Tissue samples were collected from OA patients undergoing joint replacement of the hip or knee. Nucleic acid was extracted, and, using rs143383 and an assay that discriminates and quantifies allelic expression, the relative amount of GDF5 expression from the T and C alleles was measured. Additional common variants in the GDF5 transcript sequence were interrogated as potential regulatory elements using allelic expression and luciferase reporter assays, and electrophoretic mobility shift assays were used to search for trans factors binding to rs143383. Results We observed a consistent allelic expression imbalance of GDF5 in all tissues tested, implying that the functional effect mediated by rs143383 on GDF5 expression is joint-wide. We identified a second polymorphism, located in the 3,-UTR of GDF5, that influenced allelic expression of the gene independent of rs143383. Finally, we observed differential binding of deformed epidermal autoregulatory factor 1 (DEAF-1) to the 2 alleles of rs143383. Conclusion These findings show that the OA susceptibility mediated by polymorphism in GDF5 is not restricted to cartilage, emphasizing the need to consider the disease as involving the whole joint. The existence of an additional cis -acting regulatory polymorphism highlights the complexity of the regulation of expression of this important OA susceptibility locus. DEAF-1 is a trans -acting factor that merits further investigation as a potential tool for modulating GDF5 expression. [source]


    Inflammation and angiogenesis in osteoarthritis

    ARTHRITIS & RHEUMATISM, Issue 8 2003
    L. Haywood
    Objective To quantify the relationship between inflammation and angiogenesis in synovial tissue from patients with osteoarthritis (OA). Methods Hematoxylin and eosin staining and histologic grading for inflammation were performed for 104 patients who met the American College of Rheumatology criteria for OA and had undergone total joint replacement or arthroscopy. A purposive sample of synovial specimens obtained from 70 patients was used for further analysis. Vascular endothelium, endothelial cell (EC) proliferating nuclei, macrophages, and vascular endothelial growth factor (VEGF) were detected by immunohistochemical analysis. Angiogenesis (EC proliferation, EC fractional area), macrophage fractional area, and VEGF immunoreactivity were measured using computer-assisted image analysis. Double immunofluorescence histochemical analysis was used to determine the cellular localization of VEGF. Radiographic scores for joint space narrowing and osteophyte formation in the knee were also assessed. Results Synovial tissue samples from 32 (31%) of 104 patients with OA showed severe inflammation; thickened intimal lining and associated lymphoid aggregates were often observed. The EC fractional area, EC proliferation, and VEGF immunoreactivity all increased with increasing histologic inflammation grade and increasing macrophage fractional area. In the synovial intimal lining, VEGF immunoreactivity was localized to macrophages and increased with increasing EC fractional area and angiogenesis. No inflammation or angiogenic indices were significantly correlated with radiographic scores. Conclusion Inflammation and angiogenesis in the synovium are associated with OA. The angiogenic growth factor VEGF generated by the inflamed synovium may promote angiogenesis, thereby contributing to inflammation in OA. [source]


    Reduced chondrogenic and adipogenic activity of mesenchymal stem cells from patients with advanced osteoarthritis

    ARTHRITIS & RHEUMATISM, Issue 3 2002
    J. Mary Murphy
    Objective Mesenchymal stem cells (MSCs) are resident in the bone marrow throughout normal adult life and have the capacity to differentiate along a number of connective tissue pathways, among them bone, cartilage, and fat. To determine whether functionally normal MSC populations may be isolated from patients with advanced osteoarthritis (OA), we have compared cells from patients undergoing joint replacement with cells from normal donors. Cell populations were compared in terms of yield, proliferation, and capacity to differentiate. Methods MSCs were prepared from bone marrow aspirates obtained from the iliac crest or from the tibia/femur during joint surgery. In vitro chondrogenic activity was measured as glycosaminoglycan and type II collagen deposition in pellet cultures. Adipogenic activity was measured as the accumulation of Nile Red O-positive lipid vacuoles, and osteogenic activity was measured as calcium deposition and by von Kossa staining. Results Patient-derived MSCs formed colonies in primary culture that were characteristically spindle-shaped with normal morphology. The primary cell yield in 36 of 38 cell cultures from OA donors fell within the range found in cultures from normal donors. However, the proliferative capacity of patient-derived MSCs was significantly reduced. There was a significant reduction in in vitro chondrogenic and adipogenic activity in cultures of patient-derived cells compared with that in normal cultures. There was no significant difference in in vitro osteogenic activity. There was no decline in chondrogenic potential with age in cells obtained from individuals with no evidence of OA. Conclusion These results raise the possibility that the increase in bone density and loss of cartilage that are characteristic of OA may result from changes in the differentiation profile of the progenitor cells that contribute to the homeostatic maintenance of these tissues. [source]


    Patterns of the circumflex femoral arteries revisited

    CLINICAL ANATOMY, Issue 2 2007
    M.T. Vazquez
    Abstract Knowledge of variations of the circumflex femoral arteries is important when undertaking clinical procedures within the femoral region and in hip joint replacement. Since the 19th century, many different patterns have been proposed to classify their origins. This work studied a statistically reliable sample, the lower limbs of 221 embalmed human cadavers (equal right,left and approximately equal sex distributions), and reviewed the previous literature to propose a unified and simple classification that will be useful to clinicians. Statistical comparisons were made using the ,2 test. The medial and lateral circumflex femoral arteries have been classified into three different patterns based on the levels of their origin. Distribution related to sex and side was also studied. Pattern I: Both arteries arose from the deep femoral artery (346 cases, 78.8%). This pattern was more frequent in females, P = 0.01. There was no significant difference between sides. Type Ia, medial circumflex femoral artery origin was proximal to the lateral circumflex femoral artery origin (53.2%); Type Ib, lateral circumflex femoral artery origin was proximal to medial circumflex femoral artery origin (23.4%); Type Ic, both arteries arose from a common trunk (23.4%). Pattern II: One of the arteries arose from the femoral artery and the other from the deep femoral artery (90 cases, 20.5%). Type IIa, the medial circumflex femoral artery arose from the femoral artery (77.8%) and Type IIb, the lateral circumflex femoral artery arose from the femoral artery (22.2%). There were no significant differences between sexes or sides. Pattern III: Both arteries arose from the femoral artery (2 cases, 0.5%). In every disposition there was a significantly higher prevalence of unilateral rather than bilateral occurrence. In one dissection the medial circumflex femoral artery was absent. Awareness of these variations could avoid unexpected injuries. Clin. Anat. 20:180,185, 2007. © 2006 Wiley-Liss, Inc. [source]