Low Hospital Volume Increases Re-Revision Rate Following Aseptic Revision Total Knee Arthroplasty: An Analysis of 23,644 Cases.

BACKGROUND: Along with rising numbers of primary total knee arthroplasty (TKA), the number of revision total knee arthroplasties (R-TKAs) has been increasing. R-TKA is a complex procedure requiring special instruments, implants, and surgical skills. Therefore it is likely that hospitals with more R-TKAs have more experience with this type of surgery and therefore fewer complications. The purpose of this study is to evaluate the relationship between hospital volume and re-revision rate following R-TKA. METHODS: Using nationwide healthcare insurance data for inpatient hospital treatment, 23,644 aseptic R-TKAs in 21,573 patients treated between January 2013 and December 2017 were analyzed. Outcomes were 90-day mortality, 1-year re-revision rate, and in-house adverse events. The effect of hospital volumes on outcomes were analyzed by means of multivariate logistic regression. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated. RESULTS: Hospital volume had a significant effect on 1-year re-revision rate (≤12 R-TKA/a: OR 1.44, CI 1.20-1.72; 13-24 R-TKA/a: OR 1.43, CI 1.20-1.71; 25-52 R-TKA/a: OR 1.13, CI 0.94-1.35; ≥53 R-TKA/a: reference). Ninety-day mortality and major in-house adverse events decreased with increasing volume per year, but after risk adjustment this was not statistically significant. CONCLUSION: We found evidence of higher risk for re-revision surgery in hospitals with fewer than 25 R-TKA per year. It might contribute to improved patient care if complex elective procedures like R-TKA which require experience and a specific logistic background were performed in specialized centers.

Low Hospital Volume Increases Revision Rate and Mortality Following Revision Total Hip Arthroplasty: An Analysis of 17,773 Cases.

BACKGROUND: With the number of primary total hip arthroplasty (THA), the amount of revision THA (R-THA) increases. R-THA is a complex procedure requiring special instruments, implants, and surgical skills. Therefore it is likely that hospitals performing a higher number of R-THAs have more experience with this type of surgery and therefore fewer complications. The purpose of this study was to evaluate the relationship between hospital volume and risk of postoperative complications following R-THA. METHODS: Using nationwide healthcare insurance data for inpatient hospital treatment, 17,773 aseptic R-THAs in 16,376 patients treated between January 2014 and December 2016 were included. Outcomes were 90-day mortality, 1-year revision procedures, and in-house adverse events. The effect of hospital volume on outcome was analyzed by means of multivariate logistic regression. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. RESULTS: Hospital volume had a significant effect on 90-day mortality (≤12 cases per year: OR 2.13, CI 1.53-2.96; 13-24: OR 1.79, CI 1.29-2.50; 25-52: OR 1.53, CI 1.11-2.10; ≥53: reference) and 1-year revision procedures (≤12: OR 1.26, CI 1.09-1.47; 13-24: OR 1.18, CI 1.02-1.37; 25-52: OR 1.03, CI 0.90-1.19; ≥53: reference). There was no significant effect on risk-adjusted major in-house adverse events. CONCLUSION: We found evidence of higher risk for revision surgery and mortality in hospitals with fewer than 25 and 53 R-THA per year, respectively. To improve patient care, complex elective procedures like R-THA which require experience and a specific logistic background should be performed in specialized centers.

Obesity Increases the Risk of Postoperative Complications and Revision Rates Following Primary Total Hip Arthroplasty: An Analysis of 131,576 Total Hip Arthroplasty Cases.

BACKGROUND: The aim of our study is to evaluate the association of body mass index (BMI) and the risk of postoperative complications, mortality, and revision rates following primary total hip arthroplasty given other potentially confounding patient characteristics in a large cohort study. METHODS: Using nationwide billing data for inpatient hospital treatment of the biggest German healthcare insurance, 131,576 total hip arthroplasties in 124,368 patients between January 2012 and December 2014 were included. Outcomes were 90-day mortality, 1-year revision procedures (with and without removal or exchange of implants), 90-day surgical complications, 90-day femoral fractures, and overall complications. The effect of BMI on outcome was analyzed using multivariable logistic regression. Risk-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. RESULTS: BMI had a significant effect on overall complications (30-34 in kg/m2: OR 1.1, CI 1.0-1.2, P = .014; 35-39: OR 1.5, CI 1.3-1.6, P < .001; ≥40: OR 2.1, CI 1.9-2.3, P < .001; <30: reference). The OR for 1-year revision procedures (30-34: OR 1.2, CI 1.1-1.4, P = .001; 35-39: OR 1.6, CI 1.4-1.8, P < .001; ≥40: OR 2.4, CI 2.1-2.7, P < .001; <30: reference) and 90-day surgical complications increased with every BMI category. For mortality and periprosthetic fractures there was a higher risk only for patients with BMI ≥40. CONCLUSION: BMI increases the risk of revision rates in a liner trend. Therefore, the authors believe that patients with a BMI >40 kg/m2 should be sent to obesity medicine physicians in order to decrease the body weight prior elective surgery.

Are TKAs Performed in High-volume Hospitals Less Likely to Undergo Revision Than TKAs Performed in Low-volume Hospitals?

BACKGROUND: High-volume hospitals have achieved better outcomes for THAs and unicompartmental knee arthroplasties (UKAs). However, few studies have analyzed implant survival after primary TKA in high-volume centers. QUESTIONS/PURPOSES: Is the risk of revision surgery higher when receiving a TKA in a low-volume hospital than in a high-volume hospital? METHODS: Using nationwide billing data of the largest German healthcare insurer for inpatient hospital treatment, we identified 45,165 TKAs in 44,465 patients insured by Allgemeine Ortskrankenkasse who had undergone knee replacement surgery between January 2012 and December 2012. Revision rates were calculated at 1 and 2 years in all knees. The hospital volume was calculated using volume quintiles of the number of all knee arthroplasties performed in each center. We used multiple logistic regression to model the odds of revision surgery as a function of hospital volume. Age, sex, 31 comorbidities, and variables for socioeconomic status were included as independent variables in the model. RESULTS: After controlling for socioeconomic factors, patient age, sex, and comorbidities, we found that having surgery in a high-volume hospital was associated with a decreased risk of having revision TKA within 2 years of the index procedure. The odds ratio for the 2-year revision was 1.6 (95% CI, 1.4-2.0; p < 0.001) for an annual hospital volume of 56 or fewer cases, 1.5 (95% CI, 1.3-1.7; p < 0.001) for 57 to 93 cases, 1.2 (95% CI, 1.0-1.3; p = 0.039) for 94 to 144 cases, and 1.1 (95% CI, 0.9-1.2; p = 0.319) for 145 to 251 cases compared with a hospital volume of 252 or more cases. CONCLUSIONS: We found a clear association of higher risk for revision surgery when undergoing a TKA in a hospital where less than 145 arthroplasties per year were performed. The study results could help practitioners to guide potential patients in hospitals that perform more TKAs to reduce the overall revision and complication rates. Furthermore, this study underscores the importance of a minimum hospital threshold of arthroplasty cases per year to get permission to perform an arthroplasty. LEVEL OF EVIDENCE: Level III, therapeutic study.

Blood transfusion and venous thromboembolism trends and risk factors in primary and aseptic revision total hip and knee arthroplasties: A nationwide investigation of 736,061 cases.

BACKGROUND: Over the last years, new transfusion guidelines and pharmaceuticals have been introduced in primary and revision total hip and knee arthroplasty (P-THA, P-TKA, R-THA, R-TKA). In the US, a substantial decrease in transfusions has been observed in recent years. Little data exists on the subject in Europe. In this context we aimed to analyze: (1) Is there also a significant decrease in blood transfusion for these procedures in Germany? (2) Which patient and hospital related factors are associated with the risk of blood transfusion? (3) Is there a trend in complications, especially venous thromboembolism and stroke events that can be linked to tranexamic acid use? HYPOTHESIS: There is a significant trend in decreasing blood transfusions in hip and knee arthroplasty. METHODS: Using nationwide healthcare insurance data for inpatient hospital treatment, 736,061 cases treated between January 2011 and December 2017 were included (318,997 P-THAs, 43,780 R-THAs, 338,641 P-TKAs, 34,643 R-TKAs). Multivariable logistic regression was used to model the odds of transfusion as a function of the year of surgery. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated. RESULTS: In each cohort the odds of transfusion decreased over time (2017 vs. 2011 (reference): P-THA: OR 0.42 (95%CI: 0.39-0.45), P-TKA: OR 0.41 (95%CI: 0.37-0.46), R-THA: OR 0.52 (95%CI: 0.47-0.58), R-TKA: OR 0.53 (95%CI: 0.46-0.61). Patient-related risk factors for blood transfusion included older age, female gender, lower Body Mass Index, comorbidities such as renal failure, cardiac arrhythmia, congestive heart failure, valvular disease, coagulopathy, depression, and antithrombotic medication prior to surgery. Venous thromboembolism or stroke events did not increase over the study period. DISCUSSION: The incidence of blood transfusions in primary and revision TKA and THA decreased over the study period. This may be due to new transfusion guidelines and the introduction of novel pharmaceuticals such as tranexamic acid. A further improved patient blood management and a focus on vulnerable patient groups might lead to a further future reduction of transfusions, especially in R-THA. LEVEL OF EVIDENCE: III; comparative observational study.

Dosing of Direct Oral Anticoagulants in Patients with Moderate Chronic Kidney Disease in US Clinical Practice: Results from the Outcomes Registry for Better Informed Treatment of AF (ORBIT-AF II).

INTRODUCTION: Direct oral anticoagulants (DOACs) have partial renal clearance and generally require dosage adjustments based on renal function. While current US and European guidance recommends dose adjustments in patients with moderate chronic kidney disease (CKD), it is unclear how often this is done appropriately in routine clinical practice. METHODS: We examined rates of appropriate and inappropriate dosing in patients with atrial fibrillation (AF) and moderate CKD, as determined by creatinine clearance (CrCl) of 30-50 mL/min calculated with the Cockcroft-Gault formula. Descriptive statistics were used to describe the rate of appropriate and inappropriate dosing as well as event rates. RESULTS: Among 1134 patients (8.5% of the overall ORBIT-AF II registry) with AF and CrCl 30-50 mL/min, the median age was 82 (25th, 75th percentile: 78, 86), 38% were male, and the median CHA2DS2VASC score was 4 (25th, 75th percentile: 4, 5). At baseline, more than one-third (34%) of patients with moderate CKD were inappropriately dosed with DOACs. When evaluating the specific prescribed doses in those with moderate CKD, 15% (N = 170/1134) were underdosed, 66% (743/1134) were appropriately dosed, and 20% (N = 221/1134) were overdosed. There were no significant differences in comorbid medical conditions between patients with moderate CKD who were appropriately and inappropriately dosed with a DOAC. CONCLUSION: In routine clinical practice, prescribing of DOACs in patients with AF with moderate CKD is often inconsistent with drug labeling, with up to one-third of patients being inappropriately dosed.

Relations of matrix remodeling biomarkers to blood pressure progression and incidence of hypertension in the community.

BACKGROUND: Biomarkers of extracellular matrix remodeling are associated with prevalent hypertension in cross-sectional studies, but their relations to longitudinal changes in blood pressure (BP) and hypertension incidence are unknown. METHODS AND RESULTS: We evaluated 595 nonhypertensive Framingham Offspring Study participants (mean age 55 years; 360 women) without prior heart failure or myocardial infarction who underwent routine measurements of plasma tissue inhibitor of metalloproteinase-1 (TIMP-1), metalloproteinase-9 (MMP-9), and procollagen III N-terminal peptide. We related plasma TIMP-1, procollagen III N-terminal peptide, and MMP-9 to the incidence of hypertension and progression of BP by >or=1 category (defined on the basis of the sixth report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure). On follow-up (4 years), 81 participants (51 women) developed hypertension, and 198 (114 women) progressed to a higher BP category. In multivariable models, a 1-SD increment of log-TIMP-1 was associated with a 50% higher incidence of hypertension (95% CI 1.08 to 2.08) and a 21% (95% CI 1.00 to 1.47) higher risk of BP progression. Individuals in the top TIMP-1 tertile had a 2.15-fold increased risk of hypertension (95% CI 0.99 to 4.68) and 1.68-fold (95% CI 1.05 to 2.70) increased risk of BP progression relative to the lowest tertile. Individuals with detectable MMP-9 had a 1.97-fold higher risk of BP progression (95% CI 1.06 to 3.64) than those with undetectable levels. Plasma procollagen III N-terminal peptide was not associated with hypertension incidence or BP progression. CONCLUSIONS: In the present community-based sample, higher TIMP-1 and MMP-9 concentrations were associated with BP progression on follow-up. Additional studies are warranted to confirm our findings.

[Impact of Case Numbers on the 5-Year Survival Rate of Unicondylar Knee Replacements in Germany]. / Einfluss der Fallzahl pro Klinik auf die 5-Jahres-Überlebensrate des unikondylären Kniegelenkersatzes in Deutschland.

BACKGROUND: Reported survival rates of unicondylar knee arthroplasty (UKA) vary considerably. The influences of patient characteristics and the type of implant have already been examined. This analysis investigated the influence of hospital volume on 5-year-survival rate, using administrative claims data of Germany's largest health insurance provider. METHODS: We analysed administrative claims data for 20,946 UKAs covered by the German local healthcare funds (Allgemeine Ortskrankenkasse, AOK) between 2006 and 2012. Survival rates were estimated using Kaplan-Meier analysis. The influence of hospital case numbers on 5-year survival was analysed by means of multivariable Cox regression adjusted for patient characteristics. We estimated hazard ratios (HR) with 95% confidence intervals for five hospital volume categories: < 12 cases, 13 - 24 cases, 25 - 52 cases, 53 - 104 cases, > 104 cases (per hospital and year). RESULTS: The overall 5-year Kaplan-Meier survival rate was 87.8% (95%-CI: 87.3 - 88.3%). This increased with hospital volume (< 12 cases: 84.1% vs. > 104 cases: 93.2%). The analysis identified low hospital volume as an independent risk factor for surgical revision (< 12 cases: HR = 2.13 [95%-CI 1.83 - 2.48]; 13 - 24 cases: HR = 1.94 [95%-CI: 1.67 - 2.25]; 25 - 52 cases: HR = 1.66 [95%-CI: 1.41 - 1.96]; 53 - 104 cases: HR = 1.51 [95%-CI: 1.28 - 1.77]; > 104 cases: reference category). DISCUSSION: Our analysis revealed a significant relationship between hospital case numbers and 5-year survival rate, which increases with hospital volume. The risk of surgical revision within 5 years in hospitals with fewer than 25 UKAs per year is approximately twice as high as in hospitals with more than 104 cases.

Five-Year Survival of 20,946 Unicondylar Knee Replacements and Patient Risk Factors for Failure: An Analysis of German Insurance Data.

BACKGROUND: Improvements in implant design and surgical technique of unicondylar knee arthroplasty have led to reduced revision rates, but patient selection seems to be crucial for success of such arthroplasties. The purpose of the present study was to analyze the 5-year implant survival rate of unicondylar knee replacements in Germany and to identify patient factors associated with an increased risk of revision, including >30 comorbid conditions. METHODS: Using nationwide billing data of the largest German health-care insurance for inpatient hospital treatment, we identified patients who underwent unicondylar knee arthroplasty between 2006 and 2012. Kaplan-Meier survival curves with revision as the end point and log-rank tests were used to evaluate 5-year implant survival. A multivariable Cox regression model was used to determine factors associated with revision. The risk factors of age, sex, diagnosis, comorbidities, type of implant fixation, and hospital volume were analyzed. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated. RESULTS: During the study period, a total of 20,946 unicondylar knee arthroplasties were included. The number of unicondylar knee arthroplasties per year increased during the study period from 2,527 in 2006 to 4,036 in 2012. The median patient age was 64 years (interquartile range, 56 to 72 years), and 60.4% of patients were female. During the time evaluated, the 1-year revision rate decreased from 14.3% in 2006 to 8.7% in 2011. The 5-year survival rate was 87.8% (95% CI, 87.3% to 88.3%). Significant risk factors (p < 0.05) for unicondylar knee arthroplasty revision were younger age (the HR was 2.93 [95% CI, 2.48 to 3.46] for patient age of <55 years, 1.86 [95% CI, 1.58 to 2.19] for 55 to 64 years, and 1.52 [95% CI, 1.29 to 1.79] for 65 to 74 years; patient age of >74 years was used as the reference); female sex (HR, 1.18 [95% CI, 1.07 to 1.29]); complicated diabetes (HR, 1.47 [95% CI, 1.03 to 2.12]); depression (HR, 1.29 [95% CI, 1.06 to 1.57]); obesity, defined as a body mass index of ≥30 kg/m2 (HR, 1.13 [95% CI, 1.02 to 1.26]); and low-volume hospitals, denoted as an annual hospital volume of ≤10 cases (HR, 1.60 [95% CI, 1.39 to 1.84]), 11 to 20 cases (HR, 1.47 [95% CI, 1.27 to 1.70]), and 21 to 40 cases (HR, 1.31 [95% CI, 1.14 to 1.51]) (>40 cases was used as the reference). CONCLUSIONS: Apart from known risk factors, this study showed a significant negative influence of obesity, depression, and complicated diabetes on the 5-year unicondylar knee replacement survival rate. Surgical indications and preoperative patient counseling should consider these findings. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

[BQS1 indicators as a monitoring tool for guideline implementation using selected quality indicators in the treatment of patients with breast cancer and femoral neck fractures]. / Qualitätsindikatoren der BQS als Monitoring--Instrument zur Leitlinienimplementierung am Beispiel ausgewählter Qualitätsindikatoren bei Mammakarzinom und Schenkelhalsfraktur.

Successfully implemented clinical guidelines can contribute to improvement in the quality of care. In the context of clinical guidelines, quality indicators play an important role. Quality indicators can contribute to the further development and updating of existing guidelines by analysing their results. In addition, these results support internal and external quality improvement activities and supply information on the implementation status of guideline recommendations giving an impression of the actual quality of care. In this paper the data of the mandatory German performance measurement (specimen radiograph of impalpable breast lesions, preoperative waiting time with femoral neck fracture) were analysed in respect to the extent that guideline recommendations have been implemented in clinical care. We analysed a database of 189,756 and 331,087 patients for the quality indicators 'specimen radiograph' and 'preoperative waiting time', respectively. Depending on the quality of the clinical guideline the results varied. After the publication of this recommendation as part of the German high-quality guideline for neoplasms of the breast in 2004 the proportion of radiographic controls of specimens after breast cancer surgery increased from initially 36% to 84% in 2006, and the variance as a measure of the variability of care decreased considerably. By contrast, the percentage of patients with femoral neck fracture undergoing surgery within 48h did not change noticeably (2003: 19%; 2006: 16%). A German high-quality guideline making a clear recommendation for early surgery does not yet exist. Quality indicators of the German mandatory performance measurement system are suitable for measuring the extent to which guideline recommendations have been implemented and for supporting their (further) development.

Flexible regression models are useful tools to calculate and assess threshold values in the context of minimum provider volumes.

OBJECTIVE: The aim was to review different approaches for the derivation of threshold values and to discuss their strengths and limitations in the context of minimum provider volumes. STUDY DESIGN AND SETTING: The following methods for the calculation of threshold values are compared and discussed: The value of acceptable risk limit, the value of acceptable risk gradient, the benchmark value proposed by Budtz-Jørgensen and Ulm's breakpoint model. The latter is extended to account for two different breakpoints. The methods are applied to German quality assurance data concerning total knee replacement. RESULTS: The discussed methods for calculating threshold values differ in the kind of information that has to be specified beforehand. For the value of acceptable risk limit approach an absolute number, the acceptable risk, has to be predetermined. The value of acceptable risk gradient approach and the method of Budtz-Jørgensen require the specification of a relative change expressed in gradient and in odds, respectively. On the other hand, the threshold value according to the method of Ulm is defined as a parameter of a statistical model and no a priori specification is required. CONCLUSION: Each of the proposed methods has benefits and drawbacks. The choice of the most appropriate approach depends on the specific problem and the available data.