Use Of Total Knee Replacement Research Articles

The optimized tourniquet versus no tourniquet in total knee arthroplasty. Analysis of muscle injury, functional recovery, and knee strength

BackgroundTourniquet is widely used in total knee replacement surgery because it reduces intraoperative hemorrhage and provides a comfortable surgical area for the surgeon. It's possible that its use could lead to impaired postoperative functional and motor recovery, as well as local and systemic complications. Our goal was to compare the outcomes of total knee replacement without ischemia using an optimized protocol, consisting of tourniquet inflation before skin incision and deflation after cementing, with a pressure of one hundred millimeters above systolic blood pressure and without postoperative articular suction drains.). We believed that tourniquet effectively would result in no additional muscle damage and no functional or knee strength impairment compared to no tourniquet. MethodsIn a prospective and randomized study, 60 patients with osteoarthritis were evaluated for total knee replacement, divided in two groups: 'without tourniquet' and 'optimized tourniquet'. Outcomes were mean creatine phosphokinase levels, Knee Society Score and knee isokinetic strength. Data were considered significant when p < 0.05. ResultsCreatine phosphokinase levels and functional score were similar between groups. There were no differences between groups regarding knee extension strength on the operated limbs, although the knee flexors' peak torque in the operated limb in the optimized tourniquet group was significantly higher at 6 months relative to preoperative and 3 months assessments. ConclusionsThe optimized tourniquet protocol use in total knee replacement combines the benefits of tourniquet use without compromising functional recovery and without additional muscle damage and strength deficits compared to surgery without its use.

The influence of cross shear and contact pressure on the wear of UHMWPE-on-PEEK-OPTIMA™ for use in total knee replacement

PEEK-OPTIMA™ polymer is being considered as an alternative material to cobalt chrome in the femoral component of total knee arthroplasty to give a metal-free knee replacement system. Simple geometry pin-on-plate wear simulation can be used to systematically investigate and understand the wear of materials under many different conditions. The aim of this study was to investigate the wear of UHMWPE-on-PEEK-OPTIMA™ under a range of contact pressure (2.1–80 MPa) and cross-shear ratio (0–0.18) conditions.With increasing contact pressure, there was a trend of decreasing UHMWPE wear factor with a significant difference (p<0.001) in the wear factor of UHMWPE under the different contact pressure conditions of interest. Under uniaxial motion (cross-shear ratio = 0), the wear of UHMWPE was low, introducing multi-axial motion increased the wear of the UHMWPE. There was a significant difference (p<0.01) in the wear factor at different cross-shear ratios however, post hoc analysis showed only the study carried out under unidirectional motion to be significantly different from the other conditions.With varying contact pressure and cross-shear ratio, the wear of UHMWPE against PEEK-OPTIMA™ polymer showed similar trends to previous studies of UHMWPE-on-cobalt chrome.

Effect of tourniquet use on the risk of revision in total knee replacement surgery: an analysis of the National Joint Registry Data Set

ObjectiveTourniquet use in total knee replacement (TKR) is believed to improve the bone-cement interface by reducing bleeding, potentially prolonging implant survival. This study aimed to compare the risk of revision...

Impact of a national guideline on use of knee arthroscopy: An interrupted time-series analysis.

ObjectiveTo assess the impact of the Swedish health authority recommendation against the use of knee arthroscopy in patients aged ≥40 years with knee osteoarthritis (OA).DesignInterrupted time series analysis.SettingPublic health care in Skåne region.ParticipantsPatients aged ≥40 years who underwent knee arthroscopy from January 2010 to December 2015.Intervention(s)National guideline’s recommendation against the use of knee arthroscopy in patients with knee OA.Main Outcome Measure(s)1) proportion of patients aged ≥40 years with a main diagnosis of Knee OA and/or degenerative meniscal lesions (DML) who underwent knee arthroscopy, and 2) overall knee arthroscopy rate per 100,000 Skåne population aged ≥40 years.ResultsA total of 6,155 knee arthroscopy were performed among people aged ≥40 years during study period. Of 42,044 patients with Knee OA/DML, 3,728 had knee arthroscopy. The recommendation was associated with reductions in the use of knee arthroscopy and two years after the recommendation, there was a reduction of 28.6% (95% CI: 9.3, 47.8) and 34.7% (23.9, 45.4) in proportion of Knee OA/DML patients with knee arthroscopy and the overall knee arthroscopy rate, respectively, relative to that expected if pre-recommendation trend continued. Our sensitivity analysis showed that the use of total knee replacement was stable over the study period.ConclusionThe national recommendation was associated with reduction in use of knee arthroscopy in public health care in southern Sweden. However, still 4.5% of these patients underwent knee arthroscopy in 2015 implying that more efforts are required to achieve the recommended target.

The antioxidant and non-antioxidant contributions of vitamin E in vitamin E blended ultra-high molecular weight polyethylene for total knee replacement

Vitamin E (VE) blended ultra-high molecular weight polyethylene (UHMWPE) has been developed in Japan as a material for use in total knee replacement (TKR). Various results have demonstrated that VE blended UHMWPE reduces the incidence of delamination failure and lowers the amount of wear produced during knee simulator testing. It was also found that wear particles from VE blended UHMWPE elicited a reduced biological response compared to conventional UHMWPE. A great deal of research concerning vitamin E (VE) stabilized ultrahigh molecular weight polyethylene (UHMWPE) has focused on VE's effects as an antioxidant and its ability to prevent the oxidative degradation of UHMWPE chains. However, other chemical and mechanical changes have been observed in VE blended UHMWPE that are unrelated to the oxidative protection that VE provides. This paper provides a general review of VE blended UHMWPE, with a particular focus on the non-antioxidant effects of VE. The potential application of VE blended UHMWPE in total hip replacement (THR), along with the differences in loading conditions between the knee and the hip are also discussed.

Increasing Use of Total Knee Replacement and Revision Surgery

IN THIS ISSUE OF JAMA, CRAM AND COLLEAGUES 1 report detailed analysis of primary and revision total knee replacement (TKR) performed on more than 3.2 million Medicare beneficiaries from 1991 to 2010. This analysis confirms and quantifies several important findings. First, the use of primary and revision TKRs in Medicare beneficiaries has increased both in absolute volume from 93 230 procedures in 1991 to 226 177 procedures in 2010 and in per capita usage. Second, the pattern of care has changed substantially. Between 1991 and 2010, length of hospital stay for primary TKR decreased from 7.9 to 3.5 days and revision TKR from 8.9 to 5.0 days. However, 30-day all-cause readmission rates after primary TKR increased from 4.2% in the years 1991-1994 to 5.0% in the years 2007-2010 and after revision TKR increased from 6.1% in the years 1991-1994 to 8.9% in the years 2007-2010. A clear change in the pattern of discharge status also occurred with a shift initially to a more institutionalized setting, and recently to a discharge to home with home care services (ie, discharges to patients’ homes decreased from 67.5% in the years 19911994 to 39.9% in the years 1999-2001 then increased to 56.2% in years 2007-2010). In addition to the increase in readmissions, the data demonstrated an important increase in infection rates for revision cases, increasing from 1.4% in the years 1991-1994 to 3.0% in the years 2007-2010. The first question to consider is what is driving the increased utilization. While there are different contributing factors, more importantly this report may be describing only the surface of what is expected to be a profound increase in knee arthroplasty over the next 30 years. By 2030, the demand for TKR in the United States is projected to be as high as 3.48 million procedures annually. Cram et al address only Medicare beneficiaries, but the number of younger individuals (and those without Medicare) undergoing knee replacement is also expected to continue to increase. This is particularly true considering the development of newer arthroplasty procedures used to treat degenerative arthritis in younger patients, such as bicompartmental and unicondylar knee replacements, which have been shown in select studies to be the most rapidly increasing arthroplasty treatment in this younger population. These projections will make TKR a key driver of health care cost, which makes this procedure worthy of careful consideration. This is particularly challenging given the magnitude of the predicted increase and because, as the authors discuss, many studies have demonstrated that TKR is a cost-effective procedure that may improve patients’ activity and health-related quality of life. Although health benefits are difficult to quantify, this expenditure could potentially decrease the allocation of health care resources used by patients having knee replacement over the remainder of their lifetime. Consequently, the ideal number of knee replacements that should be performed per capita is unknown. Although the study by Cram et al suggests that recent stabilization in rates of TKR procedures appears to have occurred, the authors suggest several explanations for the per capita increase, including expansion of indications and the increased prevalence of obesity, which combined with the increase in the number of patients eligible for Medicare has led to the significant increases in utilization reported. Another factor is the increased demand for an active lifestyle in this age group. Furthermore, increased efforts are needed to identify and address predisposing modifiable factors, such as obesity that lead to the need for knee replacement, and to advance efforts at early intervention strategies to treat mild arthritis and to prevent progression of the disease obviating the need for eventual arthroplasty. The cost of TKR over the next 20 years will be driven by the absolute number of primary procedures performed, the increasing number of more costly revision procedures, and

Tourniquet use in total knee replacement does not improve fixation, but appears to reduce final range of motion

Background and purpose Although a tourniquet may reduce bleeding during total knee replacement (TKA), and thereby possibly improve fixation, it might also cause complications. Migration as measured by radiostereometric analysis (RSA) can predict future loosening. We investigated whether the use of a tourniquet influences prosthesis fixation measured with RSA. This has not been investigated previously to our knowledge.Methods 50 patients with osteoarthritis of the knee were randomized to cemented TKA with or without tourniquet. RSA was performed postoperatively and at 6 months, 1 year, and 2 years. Pain during hospital stay was registered with a visual analog scale (VAS) and morphine consumption was measured. Overt bleeding and blood transfusions were registered, and total bleeding was estimated by the hemoglobin dilution method. Range of motion was measured up to 2 years.Results RSA maximal total point motion (MTPM) differed by 0.01 mm (95% CI –0.13 to 0.15). Patients in the tourniquet group had less overt bleeding (317 mL vs. 615 mL), but the total bleeding estimated by hemoglobin dilution at day 4 was only slightly less (1,184 mL vs. 1,236 mL) with a mean difference of –54 mL (95% CI –256 to 152). Pain VAS measurements were lower in the non-tourniquet group (p = 0.01). There was no significant difference in morphine consumption. Range of motion was 11° more in the non-tourniquet group (p = 0.001 at 2 years).Interpretation Tourniquet use did not improve fixation but it may cause more postoperative pain and less range of motion.

Does fibrin sealant use in total knee replacement reduce transfusion rates? A non-randomised comparative study

Studies assessing fibrin sealants use during total knee replacement (TKR) have produced inconsistent results. We evaluated fibrin sealant therapy in TKR procedures performed without tourniquet and without postoperative drains. Use of a fibrin sealant during TKR decreases calculated total blood loss, thereby diminishing blood transfusion requirements and costs. We studied 62 patients with primary knee osteoarthritis who underwent TKR by the same surgeon between September 2009 and December 2010. Fibrin sealant was used only in the last 31 patients, who were compared to the first 31 patients regarding calculated total blood loss, blood transfusion rate, and mean number of red-blood-cell units used per patient. Costs were compared in the two groups. In the control group, mean total blood loss calculated using the method of Gross was 1.3±0.6 L, 48% of patients required blood transfusions, and the mean number of units per patient was 0.9±1. In the fibrin-sealant group, 29% of patients required blood transfusions and the mean number of units was 0.6±0.9. The between-group differences in favour of the fibrin-sealant group were not statistically significant. In each group, compared with patients not requiring blood transfusions, patients needing transfusions had significantly lower starting preoperative haemoglobin values and a significantly greater positive difference between the calculated total blood loss and the maximum allowable blood loss. In the test group, the cost of the 31 units of fibrin sealant was 9743€ and the cost reduction due to using 11 fewer red-blood-cell units was only 3484€. Hospital stay was not significantly shorter in any of the two groups. Blood transfusion minimisation during TKR should rely chiefly on correcting preoperative anaemia and optimizing transfusion decisions based on the difference between the total blood loss and the maximum allowable blood loss. Fibrin sealant did not significantly diminish transfusion requirements in our study. Randomised studies in larger patient populations are needed. The cost of fibrin sealant may exceed the expected cost savings in relation with decreased blood transfusion requirements. Level III (before-after therapeutic study).

Preoperative Hemoglobin Levels, Characteristics, and Resource Utilization in Total Knee Replacement Patients with An Anemia Diagnosis Versus without An Anemia Diagnosis: An Electronic Medical Record Analysis

Abstract 2089 Purpose:This retrospective analysis describes preoperative hemoglobin (Hb) levels, characteristics, and resource use in total knee replacement (TKR) patients who had an anemia diagnosis as compared to those without an anemia diagnosis. Methods:Electronic medical records (EMR) from a large US integrated health delivery system were analyzed for the period 01/2004 to 09/2010. Adult patients with a TKR surgery record and ≥1 Hb measurement were studied. Patients with a hip or knee revision before or during surgery, with bilateral surgery, or with an emergency room (ER) visit on the surgery admission date were excluded. Patients were stratified into two groups based upon the presence or absence of an anemia diagnosis (ICD-9 codes 280.xx-285.xx) in the 90 days before or day of surgery. Hemoglobin levels measured in the 45 days prior to but excluding the day of surgery were analyzed. For patients with multiple Hb measurements, the earliest observed Hb measurement (defined as the measurement collected furthest in time from the date of surgery) was evaluated. Other clinical and demographic characteristics in the 90 days before or day of surgery and resource utilization in the 90 days pre-surgery were analyzed. Descriptive statistics were reported as frequencies and means±standard deviations, and groups were compared using the Pearson chi-square test for categorical variables and Student’s t-test for continuous variables. Results:The total study population consisted of 2,984 TKR patients, of which, 9.1% (n=273) had an anemia diagnosis. In patients with an anemia diagnosis, the first anemia diagnosis in the EMR occurred 38±30 days before surgery. Patients with an anemia diagnosis versus those without an anemia diagnosis tended to be older (mean age 70.3±10.2 vs 67.5±10.0 years, respectively; p<0.001), have a lower proportion that were white (95.2% vs 98.5%, respectively; p<0.001), and have a higher comorbidity burden as measured by the Quan-Charlson Comorbidity Index (Q-CCI) (mean Q-CCI of 1.2±1.3 vs 0.6±1.0, respectively, p<0.001). The mean earliest Hb level for the total population was 13.7±1.3 g/dL and was <13 g/dL in 28.2% of TKR patients and <12 g/dL in 9.6% of TKR patients. The mean earliest Hb level was 12.5±1.3 g/dL in patients with an anemia diagnosis and was 13.8±1.2 g/dL for the group without an anemia diagnosis (p<0.001). Of patients with an anemia diagnosis, the majority (62.3%) had an earliest Hb level <13 g/dL (versus 24.8% of those without an anemia diagnosis; p<0.001) while 33.7% of those with an anemia diagnosis had an earliest Hb level <12 g/dL (versus 7.1% of those without an anemia diagnosis; p<0.001). Seven percent of patients with an anemia diagnosis had a hospitalization in the 90 days before TKR surgery versus 3.0% of those without an anemia diagnosis (p<0.001). In addition, 5.9% of the group with an anemia diagnosis had an ER visit versus 2.8% of those without an anemia diagnosis (p=0.005). In the 90 days pre-TKR surgery, the anemia diagnosis group had 5.0±2.7 days with an office/outpatient visit and 11.9±6.0 days with another-type service (e.g., prescription refill, administrative services) while the group without an anemia diagnosis had 3.6±2.0 (p<0.001) and 7.4±4.4 (p<0.001) days with these respective services. Conclusions:In this EMR database analysis, more than 9% of patients had an anemia diagnosis based upon ICD-9 codes in 90 days before or day of TKR surgery. Patients with an anemia diagnosis differed from those without an anemia diagnosis for certain characteristics including age, proportion who were white, comorbidity burden, and mean earliest Hb levels. The proportion of patients with a hospitalization in the 90 days preceding TKR surgery was significantly greater in patients with an anemia diagnosis as compared to those without an anemia diagnosis. In the total population, over 28% and 9% of patients had an earliest Hb value <13 g/dL and <12 g/dL, respectively, however, in patients without an anemia diagnosis, over 24% and 7% had an earliest Hb level <13 g/dL and <12 g/dL, respectively. This research provides further insight into preoperative Hb levels for a population of TKR patients with and without anemia diagnosis codes. Further research is warranted to better understand these variations between groups as well as the implications of these differences on preoperative management and post-operative outcomes in TKR populations. Disclosures:Forlenza:Janssen Scientific Affairs, LLC: Employment. Ellis:Janssen Scientific Affairs, LLC: Employment. Parise:Janssen Scientific Affairs, LLC: Consultancy. Lafeuille:Janssen Scientific Affairs, LLC: Consultancy. Lefebvre:Janssen Scientific Affairs, LLC: Consultancy.

Practice guideline adherence and health care outcomes – use of prophylactic antibiotics during surgery in Taiwan

To evaluate adherence to guidelines for prophylactic antibiotic use in total knee replacement (TKR) and total hip replacement (THR) procedures and to examine the associations between guideline adherence and health care outcomes. Using nationwide health insurance claims data, all adult inpatients undergoing TKR or THR procedures at teaching hospitals from 2002 to 2006, were included. Guideline adherence rates were assessed every year according to the national guidelines introduced in 2004. Multiple regression analyses with generalized estimating equations models were used to examine the relationships between the deliberate variables. The guideline adherence rates stably increased from 14.07% in 2002 to 28.34% in 2006. The 2006 dataset included 12 863 observations. The results revealed that guideline adherence was negatively associated with length of stay and health care expenses with beta = -0.0207 and -0.0087, respectively (P < 0.0001). The 30-day readmission rate was 1.54% among the patients seen in 2006, and it was significantly different between the two groups, with 0.90% of the adherence group and 1.82% of the non-adherence group being readmitted (P = 0.0002). The guideline adherence for prophylactic use of antibiotics is improving in Taiwan and is associated with a shorter length of stay, fewer medical expenses and lower 30-day readmission rates. Promoting evidence-based practice guidelines may be beneficial to patients and health care providers.

Total Knee Replacement Part I

Total knee replacement has been one of the most common elective surgical operations in the United States for the past 20 years. The most common indication for total knee replacement is primary osteoarthritis with severe knee pain or limitation of function. Other indications include rheumatoid arthritis, posttraumatic osteoarthritis, and tumor reconstruction. Unlike total hip replacements, total knee replacement has no role in the primary treatment of fractures or dislocations of the knee. Approximately 10% of the U.S. population over age 55 years has osteoarthritis of the knee with disabling symptoms.1 As the baby boomer generation ages and moves into the prime years for joint replacement (age 50 years or older), the prevalence of total knee replacements can be expected to increase. In one study of the use of total knee replacement in western Europe, among the population over age 65 years the annual rate of total knee replacement was 0.5% to 0.7%.2 If the rate is similar in the United States, approximately 200,000 knee replacements would be performed per year in this country in patients over 65 years of age. The number of total knee replacements performed in the United States per year actually is approximately 350,000. Cost-benefit analyses have indicated that knee replacement not only is effective in eliminating pain and restoring function,3 but also is actually cost-effective compared with the alternative of pharmacologic pain control.4 Knee replacement surgery also is cost-effective at a societal level compared with common treatments such as coronary artery bypass surgery and renal dialysis.5 The knee joint replacement industry generates approximately $10 billion in revenue per year in the United States, taking into consideration only the prostheses and related instrumentation, not the patient evaluation, surgery, hospitalization, rehabilitation, or other medical costs. The total cost of a total knee replacement operation, including the prosthesis and the medical bills, is similar to that of an automobile. Direct-to-consumer marketing on the part of manufacturers of knee replacement hardware can be expected to further increase the demand for these operations in the United States. The science of joint replacement surgery currently is one of the most active areas of research in orthopaedics. Radiologists must understand when diagnostic imaging of knee replacements is appropriate, and how to perform and interpret these studies. In this first part of a two-part series on total knee replacement, we review the different types of total knee replacements and their normal appearance on imaging. In the next issue, we will review the imaging features of common complications.

Blood use in total knee replacement: Assessment of needs in contemporary surgery

Blood use in total knee replacement: Assessment of needs in contemporary surgery