Costs of Joint Replacement in Osteoarthritis: A Study Using the National Joint Registry and Clinical Practice Research Datalink Data Sets.

OBJECTIVE: To estimate the costs of primary hip and knee replacement in individuals with osteoarthritis up to 2 years postsurgery, compare costs before and after the surgery, and identify predictors of hospital costs. METHODS: Patients age ≥18 years with primary planned hip or knee replacements and osteoarthritis in England between 2008 and 2016 were identified from the National Joint Registry and linked with Hospital Episode Statistics data containing inpatient episodes. Primary care data linked with hospital outpatient records were also used to identify patients age ≥18 years with primary hip or knee replacements between 2008 and 2016. All health care resource use was valued using 2016/2017 costs, and nonparametric censoring methods were used to estimate total 1-year and 2-year costs. RESULTS: We identified 854,866 individuals undergoing hip or knee replacement. The mean censor-adjusted 1-year hospitalization costs for hip and knee replacement were £7,827 (95% confidence interval [95% CI] 7,813, 7,842) and £7,805 (95% CI 7,790, 7,818), respectively. Complications and revisions were associated with up to a 3-fold increase in 1-year hospitalization costs. The censor-adjusted 2-year costs were £9,258 (95% CI 9,233, 9,280) and £9,452 (95% CI 9,430, 9,475) for hip and knee replacement, respectively. Adding primary and outpatient care, the mean total hip and knee replacement 2-year costs were £11,987 and £12,578, respectively. CONCLUSION: There are significant costs following joint replacement. Revisions and complications accounted for considerable costs and there is a significant incentive to identify best approaches to reduce these.

Hospital volume-outcome relationship in total knee arthroplasty: a systematic review and dose-response meta-analysis.

PURPOSE: This systematic review and dose-response meta-analysis aimed to investigate the relationship between hospital volume and outcomes for total knee arthroplasty (TKA). METHODS: MEDLINE, Embase, CENTRAL and CINAHL were searched up to February 2020 for randomised controlled trials and cohort studies that reported TKA performed in hospitals with at least two different volumes and any associated patient-relevant outcomes. The adjusted effect estimates (odds ratios, OR) were pooled using a random-effects, linear dose-response meta-analysis. Heterogeneity was quantified using the I2-statistic. ROBINS-I and the GRADE approach were used to assess the risk of bias and the confidence in the cumulative evidence, respectively. RESULTS: A total of 68 cohort studies with data from 1985 to 2018 were included. The risk of bias for all outcomes ranged from moderate to critical. Higher hospital volume may be associated with a lower rate of early revision ≤ 12 months (narrative synthesis of k = 7 studies, n = 301,378 patients) and is likely associated with lower mortality ≤ 3 months (OR = 0.91 per additional 50 TKAs/year, 95% confidence interval [0.87-0.95], k = 9, n = 2,638,996, I2 = 51%) and readmissions ≤ 3 months (OR = 0.98 [0.97-0.99], k = 3, n = 830,381, I2 = 44%). Hospital volume may not be associated with the rates of deep infections within 1-4 years, late revision (1-10 years) or adverse events ≤ 3 months. The confidence in the cumulative evidence was moderate for mortality and readmission rates; low for early revision rates; and very low for deep infection, late revision and adverse event rates. CONCLUSION: An inverse volume-outcome relationship probably exists for some TKA outcomes, including mortality and readmissions, and may exist for early revisions. Small reductions in unfavourable outcomes may be clinically relevant at the population level, supporting centralisation of TKA to high-volume hospitals. LEVEL OF EVIDENCE: III. REGISTRATION NUMBER: The study was registered in the International Prospective Register of Systematic Reviews (PROSPERO CRD42019131209 available at: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=131209 ).

Long-term mortality rates and associated risk factors following primary and revision knee arthroplasty : 107,121 patients from the Scottish Arthroplasty Project.

AIMS: The aim of this study was to determine the long-term mortality rate, and to identify factors associated with this, following primary and revision knee arthroplasty (KA). METHODS: Data from the Scottish Arthroplasty Project (1998 to 2019) were retrospectively analyzed. Patient mortality data were linked from the National Records of Scotland. Analyses were performed separately for the primary and revised KA cohorts. The standardized mortality ratio (SMR) with 95% confidence intervals (CIs) was calculated for the population at risk. Multivariable Cox proportional hazards were used to identify predictors and estimate relative mortality risks. RESULTS: At a median 7.4 years (interquartile range (IQR) 4.0 to 11.6) follow-up, 27.8% of primary (n = 27,474/98,778) and 31.3% of revision (n = 2,611/8,343) KA patients had died. Both primary and revision cohorts had lower mortality rates than the general population (SMR 0.74 (95% CI 0.73 to 0.74); p < 0.001; SMR 0.83 (95% CI 0.80 to 0.86); p < 0.001, respectively), which persisted for 12 and eighteight years after surgery, respectively. Factors associated with increased risk of mortality after primary KA included male sex (hazard ratio (HR) 1.40 (95% CI 1.36 to 1.45)), increasing socioeconomic deprivation (HR 1.43 (95% CI 1.36 to 1.50)), inflammatory polyarthropathy (HR 1.79 (95% CI 1.68 to 1.90)), greater number of comorbidities (HR 1.59 (95% CI 1.51 to 1.68)), and periprosthetic joint infection (PJI) requiring revision (HR 1.92 (95% CI 1.57 to 2.36)) when adjusting for age. Similarly, male sex (HR 1.36 (95% CI 1.24 to 1.49)), increasing socioeconomic deprivation (HR 1.31 (95% CI 1.12 to 1.52)), inflammatory polyarthropathy (HR 1.24 (95% CI 1.12 to 1.37)), greater number of comorbidities (HR 1.64 (95% CI 1.33 to 2.01)), and revision for PJI (HR 1.35 (95% 1.18 to 1.55)) were independently associated with an increased risk of mortality following revision KA when adjusting for age. CONCLUSION: The SMR of patients undergoing primary and revision KA was lower than that of the general population and remained so for several years post-surgery. However, approximately one in four patients undergoing primary and one in three patients undergoing revision KA died within tenten years of surgery. Several patient and surgical factors, including PJI, were associated with the risk of mortality within ten years of primary and revision surgery. Cite this article: Bone Joint J 2022;104-B(1):45-52.

Differences in mortality and complication rates following revision knee arthroplasty performed for urgent versus elective indications.

AIMS: To compare rates of serious adverse events in patients undergoing revision knee arthroplasty with consideration of the indication for revision (urgent versus elective indications), and compare these with primary arthroplasty and re-revision arthroplasty. METHODS: Patients undergoing primary knee arthroplasty were identified in the national Hospital Episode Statistics (HES) between 1 April 1997 to 31 March 2017. Subsequent revision and re-revision arthroplasty procedures in the same patients and same knee were identified. The primary outcome was 90-day mortality and a logistic regression model was used to investigate factors associated with 90-day mortality and secondary adverse outcomes, including infection (undergoing surgery), pulmonary embolism, myocardial infarction, and stroke. Urgent indications for revision arthroplasty were defined as infection or fracture, and all other indications (e.g. loosening, instability, wear) were included in the elective indications cohort. RESULTS: A total of 939,021 primary knee arthroplasty procedures were included (939,021 patients), of which 40,854 underwent subsequent revision arthroplasty, and 9,100 underwent re-revision arthroplasty. Revision surgery for elective indications was associated with a 90-day rate of mortality of 0.44% (135/30,826; 95% confidence interval (CI) 0.37 to 0.52) which was comparable to primary knee arthroplasty (0.46%; 4,292/939,021; 95% CI 0.44 to 0.47). Revision arthroplasty for infection was associated with a much higher mortality of 2.04% (184/9037; 95% CI 1.75 to 2.35; odds ratio (OR) 3.54; 95% CI 2.81 to 4.46), as was revision for periprosthetic fracture at 5.25% (52/991; 95% CI 3.94 to 6.82; OR 6.23; 95% CI 4.39 to 8.85). Higher rates of pulmonary embolism, myocardial infarction, and stroke were also observed in the infection and fracture cohort. CONCLUSION: Patients undergoing revision arthroplasty for urgent indications (infection or fracture) are at higher risk of mortality and serious adverse events in comparison to primary knee arthroplasty and revision arthroplasty for elective indications. These findings will be important for patient consent and shared decision-making and should inform service design for this patient cohort. Cite this article: Bone Joint J 2021;103-B(10):1578-1585.

Thromboembolic and bleeding complications following primary total knee arthroplasty : a Danish nationwide cohort study.

AIMS: The aim of this study is to compare the effectiveness and safety of thromboprophylactic treatments in patients undergoing primary total knee arthroplasty (TKA). METHODS: Using nationwide medical registries, we identified patients with a primary TKA performed in Denmark between 1 January 2013 and 31 December 2018 who received thromboprophylactic treatment. We examined the 90-day risk of venous thromboembolism (VTE), major bleeding, and all-cause mortality following surgery. We used a Cox regression model to compute hazard ratios (HRs) with 95% confidence intervals (CIs) for each outcome, pairwise comparing treatment with dalteparin or dabigatran with rivaroxaban as the reference. The HRs were both computed using a multivariable and a propensity score matched analysis. RESULTS: We identified 27,736 primary TKA patients who received thromboprophylactic treatment (rivaroxaban (n = 18,846); dalteparin (n = 5,767); dabigatran (n = 1,443); tinzaparin (n = 1,372); and enoxaparin (n = 308)). In the adjusted multivariable analysis and compared with rivaroxaban, treatment with dalteparin (HR 0.68 (95% CI 0.49 to 0.92)) or dabigatran (HR 0.31 (95% CI 0.13 to 0.70)) was associated with a decreased risk of VTE. No statistically significant differences were observed for major bleeding or all-cause mortality. The propensity score matched analysis yielded similar results. CONCLUSION: Treatment with dalteparin or dabigatran was associated with a decreased 90-day risk of VTE following primary TKA surgery compared with treatment with rivaroxaban. Cite this article: Bone Joint J 2021;103-B(10):1571-1577.

Incidence and risk factors analysis for mortality after total knee arthroplasty based on a large national database in Korea.

This study aimed to analyze the rates and risk factors of postoperative mortality among 560,954 patients who underwent total knee arthroplasty (TKA) in Korea. The National Health Insurance Service-Health Screening database was used to analyze 560,954 patients who underwent TKA between 2005 and 2018. In-hospital, ninety-day, and one-year postoperative mortality, and their association with patient's demographic factors and various comorbidities (ie., cerebrovascular disease, congestive heart failure, and myocardial infarction) were assessed. In-hospital, ninety-day and one-year mortality rates after TKA were similar from 2005 to 2018. The risk of in-hospital mortality increased with comorbidities like cerebrovascular disease (hazard ratio [HR] = 1.401; 95% confidence interval [CI] = 1.064-1.844), congestive heart failure (HR = 2.004; 95% CI = 1.394 to 2.881), myocardial infarction (HR = 2.111; 95% CI = 1.115 to 3.998), and renal disease (HR = 2.641; 95% CI = 1.348-5.173). These co-morbidities were also independent predictors of ninety-day and one-year mortality. Male sex and old age were independent predictors for ninety-day and one-year mortality. And malignancy was risk factor for one-year mortality. The common preoperative risk factors for mortality in all periods were male sex, old age, cerebrovascular disease, congestive heart failure, myocardial infarction, and renal disease. Malignancy was identified as risk factor for one-year mortality. Patients with these comorbidities should be provided better perioperative care.

A comparison of comorbidity measures for predicting mortality after elective hip and knee replacement: A cohort study of data from the National Joint Registry in England and Wales.

BACKGROUND: The risk of mortality following elective total hip (THR) and knee replacements (KR) may be influenced by patients' pre-existing comorbidities. There are a variety of scores derived from individual comorbidities that can be used in an attempt to quantify this. The aims of this study were to a) identify which comorbidity score best predicts risk of mortality within 90 days or b) determine which comorbidity score best predicts risk of mortality at other relevant timepoints (30, 45, 120 and 365 days). PATIENTS AND METHODS: We linked data from the National Joint Registry (NJR) on primary elective hip and knee replacements performed between 2011-2015 with pre-existing conditions recorded in the Hospital Episodes Statistics. We derived comorbidity scores (Charlson Comorbidity Index-CCI, Elixhauser, Hospital Frailty Risk Score-HFRS). We used binary logistic regression models of all-cause mortality within 90-days and within 30, 45, 120 and 365-days of the primary operation using, adjusted for age and gender. We compared the performance of these models in predicting all-cause mortality using the area under the Receiver-operator characteristics curve (AUROC) and the Index of Prediction Accuracy (IPA). RESULTS: We included 276,594 elective primary THRs and 338,287 elective primary KRs for any indication. Mortality within 90-days was 0.34% (N = 939) after THR and 0.26% (N = 865) after KR. The AUROC for the CCI and Elixhauser scores in models of mortality ranged from 0.78-0.81 after THR and KR, which slightly outperformed models with ASA grade (AUROC = 0.77-0.78). HFRS performed similarly to ASA grade (AUROC = 0.76-0.78). The inclusion of comorbidities prior to the primary operation offers no improvement beyond models with comorbidities at the time of the primary. The discriminative ability of all prediction models was best for mortality within 30 days and worst for mortality within 365 days. CONCLUSIONS: Comorbidity scores add little improvement beyond simpler models with age, gender and ASA grade for predicting mortality within one year after elective hip or knee replacement. The additional patient-specific information required to construct comorbidity scores must be balanced against their prediction gain when considering their utility.

Fatal outcome and intensive care unit admission after total hip and knee arthroplasty: An analytic of preoperative frailty and comorbidities.

BACKGROUND: With increasing demand for total hip arthroplasty (THA) and total knee arthroplasty (TKA), a higher percentage of patients are identified with comorbidities that might increase the risk of complications. We aimed to elucidate the preoperative characteristics of patients with a fatal outcome or admission to the Intensive Care Unit (ICU) within 90 days after THA or TKA. We arbitrarily hypothesized that more than 50% of those patients would be frail. METHODS: This is a register based, explorative study including patients undergoing elective, unilateral, primary THA or TKA in the Capital Region of Denmark from 2010 to 2017, and who subsequently died or were admitted to the ICU within 90 days. The modified Frailty Index (mFI) was calculated from the medical records, and a score of ≥0.36 defined frailty. RESULTS: A total of 33,758 patients underwent THA or TKA, and 284 patients (0.8%) died or were admitted to the ICU within 90 days. Fifty-seven patients (20%) were frail (95% CI 16.2-25.7%). The most common comorbidities were hypertension (63%) and pulmonary diseases (32%), and 56% used walking aids. Two or more comorbidities were present in 65% of patients, and 14% had no comorbidities at all. CONCLUSION: Only 20% of patients with a fatal outcome or ICU admission after elective THA or TKA could be categorized as frail based on the mFI. Further studies with a prospective design are needed to clarify the mFI as a risk stratification tool in elderly multimorbid patients undergoing elective arthroplasty surgery.

Obesity and revision surgery, mortality, and patient-reported outcomes after primary knee replacement surgery in the National Joint Registry: A UK cohort study.

BACKGROUND: One in 10 people in the United Kingdom will need a total knee replacement (TKR) during their lifetime. Access to this life-changing operation has recently been restricted based on body mass index (BMI) due to belief that high BMI may lead to poorer outcomes. We investigated the associations between BMI and revision surgery, mortality, and pain/function using what we believe to be the world's largest joint replacement registry. METHODS AND FINDINGS: We analysed 493,710 TKRs in the National Joint Registry (NJR) for England, Wales, Northern Ireland, and the Isle of Man from 2005 to 2016 to investigate 90-day mortality and 10-year cumulative revision. Hospital Episodes Statistics (HES) and Patient Reported Outcome Measures (PROMs) databases were linked to the NJR to investigate change in Oxford Knee Score (OKS) 6 months postoperatively. After adjustment for age, sex, American Society of Anaesthesiologists (ASA) grade, indication for operation, year of primary TKR, and fixation type, patients with high BMI were more likely to undergo revision surgery within 10 years compared to those with "normal" BMI (obese class II hazard ratio (HR) 1.21, 95% CI: 1.10, 1.32 (p < 0.001) and obese class III HR 1.13, 95% CI: 1.02, 1.26 (p = 0.026)). All BMI classes had revision estimates within the recognised 10-year benchmark of 5%. Overweight and obese class I patients had lower mortality than patients with "normal" BMI (HR 0.76, 95% CI: 0.65, 0.90 (p = 0.001) and HR 0.69, 95% CI: 0.58, 0.82 (p < 0.001)). All BMI categories saw absolute increases in OKS after 6 months (range 18-20 points). The relative improvement in OKS was lower in overweight and obese patients than those with "normal" BMI, but the difference was below the minimal detectable change (MDC; 4 points). The main limitations were missing BMI particularly in the early years of data collection and a potential selection bias effect of surgeons selecting the fitter patients with raised BMI for surgery. CONCLUSIONS: Given revision estimates in all BMI groups below the recognised threshold, no evidence of increased mortality, and difference in change in OKS below the MDC, this large national registry shows no evidence of poorer outcomes in patients with high BMI. This study does not support rationing of TKR based on increased BMI.

Patients Undergoing Primary Total Joint Arthroplasty with Primary Hypercoagulable States.

OBJECTIVE: To analyze perioperative complications, resource consumption, and inpatient mortality of patients who receive total joint arthroplasty (TJA) with a concomitant diagnosis of a primary hypercoagulable state (PHS). The following questions were posed in the present paper. First, do patients undergoing TJA with PHS have increased risk of deep venous thrombosis (DVT), pulmonary embolism (PE), and periprosthetic joint infection (PJI)? Second, what other in-hospital complications are more likely among PHS patients undergoing TJA? Third, do TJA patients with PHS usually consume greater in-hospital resources? Fourth, do PHS patients suffer higher mortality rates compared to non-PHS patients? Finally, have PHS patients received proper anticoagulant management in past arthroplasties? METHODS: The National Inpatient Sample (NIS) database for the years between 2003 and 2014 was searched to identify patients undergoing primary TJA. Patients with PHS were identified with the ICD-9-CM code 289.81. The χ2 -test, the Pearson test, and adjusted multivariate regression analysis were performed to evaluate the difference and odds ratios between the positive and negative diagnosis groups. RESULTS: From 2003 to 2014, a total of 2,044,356 patients were identified in the NIS as undergoing primary total hip arthroplasty (THA) or total knee arthroplasty (TKA) in the United States. A total of 4664 patients (0.2%) were identified as having PHS. Compared with the non-PHS group, TJA patients with PHS had a higher risk of DVT (THA: odds ratio [OR] = 8.343, 95% CI: 5.362-12.982, P < 0.001; TKA: OR = 4.712, 95% CI: 3.560-6.238, P < 0.001) but did not have increased risk of PE (THA: OR = 1.306, 95% CI: 0.48-3.555, P = 0.602; TKA: OR = 1.143, 95% CI: 0.687-1.903), and only PHS patients in the THA group had higher risks of inpatient mortality (OR = 3.184, 95% CI: 1.348-7.522, P = 0.008) and periprosthetic joint infection (OR = 3.343, 95% CI: 1.084-10.879, P = 0.036). In addition, PHS patients had extended length of stay, higher total costs, and increased risks of certain other complications, such as peripheral vascular disease, hemorrhage, and thrombophlebitis. CONCLUSION: In the present study, PHS patients had higher risks of DVT, greater in-hospital resource consumption, and certain other perioperative complications. However, PHS was not associated with increased risk of PE in TJA patients in the United States between 2003 and 2014. While potential hazards of PHS have already been recognized, the present study revealed additional concerns and demonstrated that further improvements in the perioperative management of patients with hereditary hypercoagulable disorders are essential.

Bi-cruciate retaining total knee arthroplasty: a systematic literature review of clinical outcomes.

Total knee arthroplasty (TKA) has been shown to have good long-term outcomes and survivorship. Nonetheless, dissatisfied patients are frequently reported in the literature. Bi-cruciate retaining total knee prostheses (BCR TKA) were designed to address the demand for more kinematically functional implants that better reconstruct natural knee kinematics. In BCR TKA, the anterior cruciate ligament (ACL) is preserved. Improved patient-reported outcomes and satisfaction levels are expected. This review aimed to summarize indications for and clinical outcomes of BCR TKA. A systematic literature review on BCR TKA was performed. 24 articles were included for data analysis. Indications covered osteoarthritis, inflammatory arthritis and others. The degree of deformity was often but not always limited to minor axial deformity and contractures: maximum acceptable varus/valgus deformity reached 10°-30° and flexion contractures of 15°-65°. ACL intactness was macroscopically examined intraoperatively in nine studies and clinically tested in ten studies (e.g., Lachmann Test, drawer-test). Objective and patient-reported outcome scores were reported for follow-up periods of up to 22 years. Survival rates varied significantly. For first generation implants, 22-year survival reached 82% while a second generation design was associated with 13.5% revision rate at 18 months. Reasons for varying outcomes were not clear and may be attributed to the implant itself, surgical techniques and patient specific variables including changed expectations and functional demand. The literature has not shown clear indications and guidelines for the use of BCR implants. The promising results of first generation BCR TKA designs may be optimized through improved implant designs in the future. Further studies are advocated to provide the necessary evidence of second generation BCR TKA designs.

Postoperative Morbidity and Mortality in Diabetic Patients After Fast-Track Hip and Knee Arthroplasty: A Prospective Follow-up Cohort of 36,762 Procedures.

BACKGROUND: Diabetes increases the risk of adverse outcomes in surgical procedures, including total hip and knee arthroplasty (THA/TKA), and the prevalence of diabetic patients undergoing these procedures is high, ranging from approximately 8% to 20%. However, there is still a need to clarify the role of diabetes and antihyperglycemic treatment in a fast-track THA/TKA setting, which otherwise may decrease morbidity. Consequently, we investigated the association between diabetes and antihyperglycemic treatment on length of stay (LOS) and complications following fast-track THA/TKA within a multicenter fast-track collaboration. METHODS: We used an observational study design on data from a prospective multicenter fast-track collaboration on unselected elective primary THA/TKA from 2010 to 2017. Complete follow-up (>99%) was achieved through The Danish National Patient Registry, antihyperglycemic treatment established through the Danish National Database of Reimbursed Prescriptions and types of complications leading to LOS >4 days, 90-day readmission or mortality obtained by scrutinizing health records and discharge summaries. Patients were categorized as nondiabetic and if diabetic into insulin-, orally, and dietary-treated diabetic patients. RESULTS: A total of 36,762 procedures were included, of which 837 (2.3%) had insulin-treated diabetes, 2615 (7.1%) orally treated diabetes, and 566 (1.5%) dietary-treated diabetes. Overall median LOS was 2 (interquartile range [IQR]: 1-3) days, and mean LOS was 2.4 (standard deviation [SD], 2.5) days. The proportion of patients with LOS >4 days was 6.0% for nondiabetic patients, 14.7% for insulin-treated, 9.4% for orally treated, and 9.5% for dietary-treated diabetic patients. Pharmacologically treated diabetes (versus nondiabetes) was independently associated with increased odds of LOS >4 days (insulin-treated: odds ratio [OR], 2.2 [99.6% confidence interval {CI}, 1.3-3.7], P < .001; orally treated: OR, 1.5 [99.6% CI, 1.0-2.1]; P = .002). Insulin-treated diabetes was independently associated with increased odds of "diabetes-related" morbidity (OR, 2.3 [99.6% CI, 1.2-4.2]; P < .001). Diabetic patients had increased renal complications regardless of antihyperglycemic treatment, but only insulin-treated patients suffered significantly more cardiac complications than nondiabetic patients. There was no increase in periprosthetic joint infections or mortality associated with diabetes. CONCLUSIONS: Patients with pharmacologically treated diabetes undergoing fast-track THA/TKA were at increased odds of LOS >4 days. Although complication rates were low, patients with insulin-treated diabetes were at increased odds of postoperative complications compared to nondiabetic patients and to their orally treated counterparts. Further investigation into the pathogenesis of postoperative complications differentiated by antihyperglycemic treatment is needed.

Risk of a complete exchange or failure in total knee arthroplasty and unicompartmental knee arthroplasty: a nationwide population-based cohort study from South Korea.

PURPOSE: Few large-scale studies using adjusted data from national registries have explored the risk factors of subsequent revision in patients with unicompartmental knee arthroplasty (UKA) compared to those with total knee arthroplasty (TKA). We investigated the incidence rate and risk factors of subsequent revision in patients with UKA and TKA. METHODS: We enrolled all patients who had undergone TKA or UKA as the primary surgical procedure without histories of having undergone either procedure during the preceding 2 years. Matched Cox regression models were used to compare the risks of revision between groups after propensity score matching. Revision was defined as conversion to revision TKA after primary TKA and conversion to TKA after UKA. RESULTS: The study enrolled 418,806 TKA patients and 446,009 UKA patients. The risk of revision during the entire study period was higher for patients with UKA than for patients with TKA (adjusted hazard ratio [HR] 1.22, 95% confidence interval [95% CI]: 1.10-1.36). The Kaplan-Meier 8-year survival was 98.7% in the TKA group and 96.7% in the UKA group. Patients with UKA were at an increased risk of revision in cases of advanced age (70-79 years, HR 1.40, 95% CI: 1.15-1.71), female sex (HR 1.32, 95% CI: 1.16-1.49), the presence of chronic obstructive pulmonary disease (COPD) (HR 1.27, 95% CI: 1.05-1.54), the presence of peptic ulcer disease (PUD) (HR 1.34, 95% CI: 1.11-1.61) compared to patients with TKA. In patients with hemiplegia, however, UKA were associated with a lower risk of subsequent revision (HR 0.25, 95% CI: 0.07-0.94). CONCLUSION: The risk of a complete exchange or failure was higher for patients with UKA than for patients with TKA. The most significant independent risk factors for subsequent a complete exchange or failure in patients with UKA were advanced age (70-79 years), female sex, and the presence of comorbidities such as COPD and PUD.

Mortality after hip or knee arthroplasty for osteoarthritis in Chile: A survival analysis.

BACKGROUND: The purpose of this study is to determine if patients with osteoarthritis that undergo hip or knee arthroplasty jeopardize their life expectancy in Chile. METHODS: A survival analysis study was designed and approved by our institutional ethics review board. Patients were included if they underwent surgery for hip or knee osteoarthritis and were 50 years or older at the time of surgery. Patients were excluded if arthroplasty was performed for fracture, hemophilia arthropathy, or tumor. A multiparametric Weibull regression was estimated, and the hazard ratio was reported. For internal validity, a bootstrap of 200 repetitions was performed. RESULTS: A total of 4 094 arthroplasties were included. The Kaplan-Meier curve estimates a higher survival than the general population up to 12 years, after which the median survival is less than the general population. The bootstrap multiparametric Weibull regression estimated a hazard ratio of 1.53 (95% confidence interval: 1.27 to 1.84) for women, 1.09 (1.08 to 1.10) for every year older, and 1.29 (1.07 to 1.53) for hip arthroplasty patients. CONCLUSION: Mortality after hip and knee arthroplasty in Chile follows a bimodal behavior similar to reports from the United States and Europe. At first, mortality is lower than the general population but worsens after 12 to 15 years of surgery.

INTRODUCCIÓN: El propósito de este estudio es determinar si los pacientes con artrosis severa intervenidos con artroplastia de rodilla o cadera ponen en riesgo su expectativa de vida. MÉTODO: Se diseñó un estudio de sobrevida el cual fue aprobado por el comité de ética de nuestra institución. Los pacientes fueron incluidos si fueron intervenidos de artroplastia de rodilla y cadera por artrosis severa y tenían más de 50 años. Los pacientes fueron excluidos si la artroplastia se realizó por fractura, hemofilia o un tumor. Una regresión multiparamétrica de Weibull fue estimada, siendo reportado el hazard ratio. Un bootstrap de 200 repeticiones fue realizada para validación interna. RESULTADOS: Un total de 4094 artroplastias fueron incluidos. La curva de Kaplan-Meier estima una mayor sobrevida que la población general hasta los 12 años, luego de lo cual la mediana de sobrevida es menor que la de la población general. La regresión multiparamétrica de Weibull estimó hazard ratios de 1,53 (intervalo de confianza 95%: 1,27 a 1,84) en mujeres, de 1,09 (1,08 a 1,10) por cada año de edad y de 1,29 (1,07 a 1,53) en artroplastia de cadera. CONCLUSIÓN: La mortalidad después de una intervención de artroplastia de rodilla o cadera sigue un comportamiento bimodal respecto a la población general similar a series reportadas en Estados Unidos y Suecia. Inicialmente la sobrevida es mayor que la población general, pero es menor luego de 12 a 15 años.

Does patellofemoral osteoarthritis affect functional outcomes and survivorship after medial unicompartmental knee arthroplasty? A meta-analysis.

PURPOSE: The argument that patellofemoral osteoarthritis (PFOA) is a contraindication to unicompartmental knee arthroplasty (UKA) remains to be resolved. The purpose of this study was to perform a meta-analysis to determine whether PFOA affects functional outcomes and survivorship after medial UKA. METHODS: A literature search was performed in PubMed, Medline, Cochrane Library and Web of science to identify studies published in English (the last search was updated on June 1, 2020). The primary outcome measure was the Oxford Knee Score (OKS), whereas the secondary outcomes included range of motion (ROM) and the revision rate. Patients with patellofemoral joint narrowing or cartilage lesions as assessed intraoperatively or by radiography were assigned to the PFOA group. RESULTS: A total of 8 studies involving 3504 patients and 3975 knees were included in this meta-analysis. No patients had a severe lateral patellar groove. The results showed that there was no significant difference in the OKS, revision rate and ROM between PFOA patients and patients without PFOA. CONCLUSIONS: No significant difference in functional outcomes and survivorship was found between patients with and without PFOA. Patients with PFOA assessed by radiographs or intraoperatively but without a lateral patellar groove should be considered candidates for medial UKA.

Improvement in fast-track hip and knee arthroplasty: a prospective multicentre study of 36,935 procedures from 2010 to 2017.

"Fast-track" protocols has improved surgical care with a reduction in length of hospital stay (LOS) in total hip (THA) and knee arthroplasty (TKA). However, the effects of continuous refinement of perioperative care lack detailed assessment. We studied time-related changes in LOS and morbidity after THA and TKA within a collaboration with continuous scientific refinement of perioperative care. Prospective multicentre consecutive cohort study between 2010 and 2017 from nine high-volume orthopaedic centres with established fast-track THA and TKA protocols. Prospective collection of comorbidities and complete 90-day follow-up from the Danish National Patient Registry and medical records. Of 36,935 procedures median age was 69 [62 to 75] years and 58% women. LOS declined from three [two to three] days in 2010 to one [one to two] day in 2017. LOS > 4 days due to "medical" or "surgical" complications, and "with no recorded morbidity" declined from 4.4 to 2.7%, 1.5 to 0.6%, and 3.8 to 1.3%, respectively. 90-days readmission rate declined from 8.6 to 7.7%. Our multicentre study in a socialized healthcare setting was associated with a continuous reduction in LOS and morbidity after THA and TKA.

Mortalidad de los pacientes intervenidos de artroplastia de rodilla y cadera en Chile: análisis de sobrevida / Mortality after hip or knee arthroplasty for osteoarthritis in Chile: a survival analysis

Introducción El propósito de este estudio es determinar si los pacientes con artrosis severa intervenidos con artroplastia de rodilla o cadera ponen en riesgo su expectativa de vida. Método Se diseñó un estudio de sobrevida el cual fue aprobado por el comité de ética de nuestra institución. Los pacientes fueron incluidos si fueron intervenidos de artroplastia de rodilla y cadera por artrosis severa y tenían más de 50 años. Los pacientes fueron excluidos si la artroplastia se realizó por fractura, hemofilia o un tumor. Una regresión multiparamétrica de Weibull fue estimada, siendo reportado el hazard ratio. Un bootstrap de 200 repeticiones fue realizada para validación interna. Resultados Un total de 4094 artroplastias fueron incluidos. La curva de Kaplan-Meier estima una mayor sobrevida que la población general hasta los 12 años, luego de lo cual la mediana de sobrevida es menor que la de la población general. La regresión multiparamétrica de Weibull estimó hazard ratios de 1,53 (intervalo de confianza 95%: 1,27 a 1,84) en mujeres, de 1,09 (1,08 a 1,10) por cada año de edad y de 1,29 (1,07 a 1,53) en artroplastia de cadera. Conclusión La mortalidad después de una intervención de artroplastia de rodilla o cadera sigue un comportamiento bimodal respecto a la población general similar a series reportadas en Estados Unidos y Suecia. Inicialmente la sobrevida es mayor que la población general, pero es menor luego de 12 a 15 años.

Background The purpose of this study is to determine if patients with osteoarthritis that undergo hip or knee arthroplasty jeopardize their life expectancy in Chile. Methods A survival analysis study was designed and approved by our institutional ethics review board. Patients were included if they underwent surgery for hip or knee osteoarthritis and were 50 years or older at the time of surgery. Patients were excluded if arthroplasty was performed for fracture, hemophilia arthropathy, or tumor. A multiparametric Weibull regression was estimated, and the hazard ratio was reported. For internal validity, a bootstrap of 200 repetitions was performed. Results A total of 4 094 arthroplasties were included. The Kaplan-Meier curve estimates a higher survival than the general population up to 12 years, after which the median survival is less than the general population. The bootstrap multiparametric Weibull regression estimated a hazard ratio of 1.53 (95% confidence interval: 1.27 to 1.84) for women, 1.09 (1.08 to 1.10) for every year older, and 1.29 (1.07 to 1.53) for hip arthroplasty patients. Conclusion Mortality after hip and knee arthroplasty in Chile follows a bimodal behavior similar to reports from the United States and Europe. At first, mortality is lower than the general population but worsens after 12 to 15 years of surgery.

Better outcomes and reduced failures for arthroplasty over osteotomy for advanced compartmental knee osteoarthritis in patients older than 50 years.

BACKGROUND: Both compartmental knee arthroplasty (CKA) and open-wedge high tibial osteotomy (HTO) may be used to treat patients older than 50 years of age with advanced compartmental osteoarthritis (OA) secondary to leg axis deformities. A meta-analysis was conducted to clarify the role of open-wedge HTO versus CKA for patients older than 50 years with advanced compartmental knee OA. The present investigation aimed to analyse the clinical outcomes, implant failure and survivorship. METHODS: This meta-analysis was performed in accordance with the PRISMA guidelines. In September 2020, the main online databases were accessed. All clinical trials comparing the outcomes of open-wedge HTO versus CKA for compartmental knee OA were considered. Data analysis was performed through the Review Manager Software 5.3 (the Nordic Cochrane Collaboration, Copenhagen). Implant survivorship was analysed with a Kaplan-Meier (KM) curve that was performed using the STATA/MP software (StataCorp, College Station, TX). RESULTS: Data from 618 (HTO, 307; CKA, 311) patients were collected. Good baseline comparability among patient age, BMI and gender was detected. The Tegner Activity Scale was higher in the CKA group (P = 0.04), as were the Lysholm score (P = 0.001), the International Knee Documentation Committee (P = 0.0001) and the Knee injury and Osteoarthritis Outcome Score (P = 0.05). At a mean follow-up of 5 years, revisions were less in the CKA cohort (OR, 2.27; P = 0.004). The Kaplan-Meier curve evidenced longer implant survivorship in favour of the CKA group (P = 0.01). CONCLUSION: In patients older than 50 years of age with compartmental knee OA secondary to frontal axis leg deformities, CKA performed better than open-wedge HTO.

Five years' trajectories of functionality and pain in patients after hip or knee replacement and association with long-term patient survival.

To describe the 5 years' trajectories in functionality and pain of patients with hip or knee osteoarthritis and arthroplasty and analyze the association of these with long-term patients survival. Patients with OA receiving total hip or knee arthroplasty were recruited and completed two sets of standardized questionnaires for functionality and pain 6, 12, and 60 months postoperatively. Multivariate mixed models were conducted to assess trajectories over time and the resulting improvement per month during the last time period was included in a landmark-model to estimate adjusted hazard ratios for mortality. In total 809 patients with joint replacement were included (mean age 65.0 years, 62.2% female), 407 patients died (median follow-up 18.4 years). Both instruments of functionality and pain showed extensive improvement during the first 6 months. Baseline and change in functionality (both p < 0.001) and pain (p = 0.02) during the first 6 months were associated with mortality. Better values in functionality corresponded with improved survival whereas the association with the pain scores was inverse. In patients with hip and knee OA, an explicit improvement in function is seen within the first 6 months after arthroplasty. In addition, especially the functionality scores at baseline as well as their improvement showed an association with long-term patient survival.

Current Evidence-based Indications for Modern Noncemented Total Knee Arthroplasty.

Total knee arthroplasty (TKA) is one of the most common procedures performed in orthopaedic surgery. Traditionally, most TKAs have been performed by cementing the implant to the bone with polymethyl methacrylate to provide fixation. Noncemented implants that rely on boney ingrowth for fixation are increasingly appealing to surgeons, given success in total hip arthroplasty and the desire for long-term stability of implants in younger patients. Despite high failure rates with early designs, several series of recent designs have demonstrated improved survivorship, although this has not been confirmed in larger registry studies. Modern screwless designs with improved porous coating are thought to contribute to better ingrowth and have been designed to address previous implant pitfalls. Surgeons must be aware of the potential advantages and limitations of noncemented TKA.