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.

No increased mortality after total hip arthroplasty in patients with a history of pediatric hip disease: a matched, population-based cohort study on 4,043 patients.

Background and purpose - Patients with pediatric hip diseases are more comorbid than the general population and at risk of premature, secondary osteoarthritis, often leading to total hip arthroplasty (THA). We investigated whether THA confers an increased mortality in this cohort.Patients and methods - We identified 4,043 patients with a history of Legg-Calvé-Perthes disease (LCPD), slipped capital femoral epiphysis (SCFE), or developmental dysplasia of the hip (DDH) in the Swedish Hip Arthroplasty Register (SHAR) between 1992 and 2012. For each patient, we matched 5 controls from the general population for age, sex, and place of residence, and acquired information on all participants' socioeconomic background and comorbidities. Mortality after THA was estimated according to Kaplan-Meier, and Cox proportional hazard models were fitted to estimate adjusted hazard ratios (HRs) for the risk of death.Results - Compared with unexposed individuals, patients exposed to a THA due to pediatric hip disease had lower incomes, lower educational levels, and a higher degree of comorbidity but a statistically non-significant attenuation of 90-day mortality (HR 0.9; 95% CI 0.4-2.0) and a lower risk of overall mortality (HR 0.8; CI 0.7-0.9).Interpretation - Patients exposed to THA due to a history of pediatric hip disease have a slightly lower mortality than unexposed individuals. THA seems not to confer increased mortality risks, even in these specific patients with numerous risk factors.

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.

Impact of socioeconomic status on the 90- and 365-day rate of revision and mortality after primary total hip arthroplasty: a cohort study based on 103,901 patients with osteoarthritis from national databases in Denmark.

Background and purpose - Socioeconomic inequality in health is recognized as an important public health issue. We examined whether socioeconomic status (SES) is associated with revision and mortality rates after total hip arthroplasty (THA) within 90 and 365 days.Patients and methods - We obtained SES markers (cohabitation, education, income, and liquid assets) on 103,901 THA patients from Danish health registers (year 1995-2017). The outcomes were any revision (all revisions), specified revision (due to infection, fracture, or dislocation), and mortality. We used Cox regression analysis to estimate adjusted hazard ratio (aHR) of each outcome with 95% confidence interval (CI) for each SES marker.Results - Within 90 days, the aHR for any revision was 1.3 (95% CI 1.1-1.4) for patients living alone vs. cohabiting. The aHR was 2.0 (CI 1.4-2.6) for low-income vs. high-income among patients < 65 years. The aHR was 1.2 (CI 0.9-1.7) for low liquid assets among patients > 65 years. Results were consistent for any revision within 365 days as well as for revisions due to infection, fracture, and dislocation. The aHR for mortality was 1.4 (CI 1.2-1.6) within 90 days and 1.3 (CI 1.2-1.5) within 365 days for patients living alone vs. cohabiting. Low education, low income, and low liquid assets were associated with increased mortality rate within both 90 and 365 days.Interpretation - Our results suggest that living alone, low income, and low liquid assets were associated with increased revision and mortality up to 365 days after THA surgery. Optimizing medical conditions prior to surgery and implementing different post-THA support strategies with a focus on vulnerable patients may reduce complications associated with inequality.

Comparison of Peripheral Nerve Block and Spinal Anesthesia in Terms of Postoperative Mortality and Walking Ability in Elderly Hip Fracture Patients - A Retrospective, Propensity-Score Matched Study.

PURPOSE: To compare the effects of peripheral nerve block (PNB) and spinal anesthesia (SA) on one-year mortality and walking ability of elderly hip fracture patients after hip arthroplasty. METHODS: Patients ≥65 years who underwent unilateral hip arthroplasty due to femoral neck fracture, using either PNB or SA from 2014 to 2019, were included. Demographic data, comorbidities, and results of preoperative screening were retrospectively collected. Propensity score matching (PSM) was performed in a ratio of 1:1 for PNB and SA groups. The primary outcomes were 30-day, 90-day, and one-year mortality. Secondary outcomes included walking ability in the first postoperative year, major complications, length of stay, and the cost of hospitalization. Survival analysis was performed using Kaplan-Meier method. RESULTS: Three hundred and sixteen patients were included, of whom 200 received SA and 116 received PNB. Eighty-nine patients in each group were matched after PSM. Patients in the PNB group showed significantly lower risks of death in 30 days (2.2% vs 10.1%, P=0.029) and 90 days (3.4% vs 12.4%, P=0.026) after hip arthroplasty, when compared to the SA group. There was no significant difference in one-year mortality, walking ability, major complications, and length of stay. Higher hospitalization cost was found in the PNB group (53,828.21 CNY vs 59,278.83 CNY, P=0.024). One-year accumulated survival rate was higher in the PNB group without reaching a significant level. CONCLUSION: PNB was related to lower 30- and 90-day mortality but higher hospitalization cost in elderly hip fracture patients after hip arthroplasty. However, the anesthesia types were not associated with one-year mortality, one-year walking ability, major complications, and length of stay.

Minimum 15-year results of metasul 28-mm metal-on-metal total hip arthroplasty in patients younger than 50 years of age.

BACKGROUND: Some propitious mid- and long-term studies had been reported for MoM bearings; however, most studies have addressed specific patient groups rather than younger, active patients, who probably represent the most suitable population for investigations on wear and osteolysis. The purpose of this study to evaluate the long-term results of second-generation metal-on-metal cementless total hip arthroplasty (THA) in patients aged <50 years. METHODS: From December 1997 to January 2004, primary THA using a metal-on-metal bearing cementless implant was performed in 63 patients (72 hips) aged <50 years. The mean follow-up duration was 18.6 (range, 15.9-22.1) years, and the mean age at initial operation was 39 (range, 22-49) years. Clinical results, complications, survivorship, osteolysis, and aseptic loosening were evaluated. RESULTS: The mean Harris hip score and Western Ontario and McMaster Universities Arthritis Index scores were improved from 57.8 (range, 28-69) points and 73.4 (range, 63-94) points preoperatively to 91.7 (range, 80-100) points and 25.5 points (range, 17-38) points, respectively, at the last follow-up. Osteolysis lesions were found in 12 hips (acetabulum, 6 and femur, 6). The notching occurred on the femoral stem neck occurred in 12 hips. The mean serum cobalt and chromium concentrations were 2.3 (range, 0.2-10.6) µg/L and 1.7 (range, 0.4-8.1) µg/L, respectively, at a mean follow-up of 12.7 years in 32 patients (50.1%). The Kaplan-Meier survivorship curve analysis with revision for any reason as the endpoint revealed that 93.1% survived at 18.6 years' follow-up. CONCLUSIONS: Second-generation metal-on-metal cementless THA was found to produce satisfactory clinical and radiographic results with a low revision rate for osteolysis and aseptic loosening in patients aged less than 50 years.

Prediction of 90-day mortality after total hip arthroplasty.

AIMS: To develop and externally validate a parsimonious statistical prediction model of 90-day mortality after elective total hip arthroplasty (THA), and to provide a web calculator for clinical usage. METHODS: We included 53,099 patients with cemented THA due to osteoarthritis from the Swedish Hip Arthroplasty Registry for model derivation and internal validation, as well as 125,428 patients from England and Wales recorded in the National Joint Register for England, Wales, Northern Ireland, the Isle of Man, and the States of Guernsey (NJR) for external model validation. A model was developed using a bootstrap ranking procedure with a least absolute shrinkage and selection operator (LASSO) logistic regression model combined with piecewise linear regression. Discriminative ability was evaluated by the area under the receiver operating characteristic curve (AUC). Calibration belt plots were used to assess model calibration. RESULTS: A main effects model combining age, sex, American Society for Anesthesiologists (ASA) class, the presence of cancer, diseases of the central nervous system, kidney disease, and diagnosed obesity had good discrimination, both internally (AUC = 0.78, 95% confidence interval (CI) 0.75 to 0.81) and externally (AUC = 0.75, 95% CI 0.73 to 0.76). This model was superior to traditional models based on the Charlson (AUC = 0.66, 95% CI 0.62 to 0.70) and Elixhauser (AUC = 0.64, 95% CI 0.59 to 0.68) comorbidity indices. The model was well calibrated for predicted probabilities up to 5%. CONCLUSION: We developed a parsimonious model that may facilitate individualized risk assessment prior to one of the most common surgical interventions. We have published a web calculator to aid clinical decision-making. Cite this article: Bone Joint J 2021;103-B(3):469-478.

International variation in distribution of ASA class in patients undergoing total hip arthroplasty and its influence on mortality: data from an international consortium of arthroplasty registries.

Background and purpose - A challenge comparing outcomes from total hip arthroplasty between countries is variation in preoperative characteristics, particularly comorbidity. Therefore, we investigated between-country variation in comorbidity in patients based on ASA class distribution, and determined any variation of ASA class to mortality risk between countries.Patients and methods - All arthroplasty registries collecting ASA class and mortality data in patients with elective primary THAs performed 2012-2016 were identified. Survival analyses of the influence of ASA class on 1-year mortality were performed by individual registries, followed by meta-analysis of aggregated data.Results - 6 national registries and 1 US healthcare organization registry with 418,916 THAs were included. There was substantial variation in the proportion of ASA class III/IV, ranging from 14% in the Netherlands to 39% in Finland. Overall, 1-year mortality was 0.93% (95% CI 0.87-1.01) and increased from 0.2% in ASA class I to 8.9% in class IV. The association between ASA class and mortality measured by hazard ratios (HR) was strong in all registries even after adjustment for age and sex, which reduced them by half in all registries. Combined adjusted HRs were 2.0, 6.1, and 22 for ASA class II-IV vs. I, respectively. Associations were moderately heterogeneous across registries.Interpretation - We observed large variation in ASA class distribution between registries, possibly explained by differences in background morbidity and/or international variation in access to surgery. The similar, strong mortality trends by ASA class between countries enhance the relevance of its use as an indicator of comorbidity in international registry studies.

Outcomes of hip arthroplasty with concomitant hardware removal: influence of the type of implant retrieved and impact of positive intraoperative cultures.

INTRODUCTION: The impact of residual internal fixation devices on subsequent procedures about the hip has not been clearly well defined. The objective of the current study is to evaluate the outcome of hip arthroplasty after hardware retrieval as a one-stage replacement, to analyze possible differences related to the type of removed implant, and to assess the impact of unexpected intraoperative cultures during implant retrieval. MATERIALS AND METHODS: We present a retrospective study including all those cases undergoing hip arthroplasty with concomitant hardware removal (cannulated screws, intramedullary nail, or dynamic hip screw) from 2005 to 2018. We evaluated demographics, intraoperative cultures, early infection rate, and other complications. RESULTS: A total of 55 cases were included in the study. The median time between the implant surgery and the hip arthroplasty was 113 days. The removed devices included 6 cannulated screws, 34 intramedullary nails, and 15 dynamic hip screws. Up to 74.5% of the failed osteosynthesis belonged to intertrochanteric femoral fractures. Dislocation rate was 9.1% (1.8% requiring revision surgery), 25.5% of the cases needed further new surgeries after the hip arthroplasty, and 49.1% died during the follow-up period. Any-cause revision surgery and mortality rates were significantly increased after intramedullary nail removal. Intraoperative cultures were performed in 46 cases, and in 9 (16.4%), there was bacterial contamination: 6 cases (10.9%) presented one single positive culture and 3 (5.5%) presented ≥ 2 positive cultures for the same microorganism. A total of five cases (9.1%) presented early prosthetic joint infection that required debridement. None of these five cases had presented positive cultures at the implant removal. CONCLUSION: According to our results, hip arthroplasty with concomitant hardware removal is related to a high 5-year mortality rate, mainly when intramedullary nail is retrieved. Whereas a high risk of early prosthetic joint infection is associated, it seems not to be related to the elevated presence of unexpected positive cultures.

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.

Similar early mortality risk after cemented compared with cementless total hip arthroplasty for primary osteoarthritis: data from 188,606 surgeries in the Nordic Arthroplasty Register Association database.

Background and purpose - Current literature indicates no difference in 90-day mortality after cemented compared with cementless total hip arthroplasty (THA). However, previous studies are hampered by potential selection bias and suboptimal adjustment for comorbidity confounding. Therefore, we examined the comorbidity-adjusted mortality up to 90 days after cemented compared with cementless THA performed due to osteoarthritis.Patients and methods - Using the Nordic Arthroplasty Register Association database, 2005-2013, we included 108,572 cemented and 80,034 cementless THA due to osteoarthritis. We calculated the Charlson comorbidity index of each patient based on data from national patient registers. The Kaplan-Meier method was used to estimate unadjusted all-cause mortality. Cox regression was used to estimate hazard ratios (HR) with 95% confidence intervals (CI) for 14, 30-, and 90-day mortality comparing cemented with cementless THA, adjusting for age, sex, comorbidity, nation, and year of surgery.Results - Cumulative all-cause mortality within 90 days was 0.41% (CI 0.37-0.46) after cemented and 0.26% (CI 0.22-0.30) after cementless THA. The adjusted HR for cemented vs. cementless fixation was 0.97 (CI 0.79-1.2), and similar risk estimates were obtained for mortality within 14 (adjusted HR 0.91 [CI 0.64-1.3]) and 30 days (adjusted HR 0.94 [CI 0.71-1.3]). We found no clinically relevant differences in mortality between cemented and cementless THA in analyses stratified by age, sex, Charlson comorbidity index, or year of surgery.Interpretation - After adjustment for comorbidity as an important confounder, we observed similar early mortality between the 2 fixation techniques.

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.

The majority of conversion total hip arthroplasties can be considered a primary replacement: a matched cohort study.

BACKGROUND AND STUDY AIMS: The success of conversion total hip arthroplasty (THA) among primary THA and revision THA remains unclear. We hypothesized that most conversion THA's can be performed using primary implants and will have an uncomplicated post-operative course. MATERIALS AND METHODS: Thirty-six patients (23 females, mean age 68,0y) who underwent conversion THA for failed interventions for proximal femur fractures in the period 2008-2018 were matched sequentially against patients of the same sex and age who underwent primary THA or revision THA. Data were collected on implants used, major complications, and mortality. PROMs used included the Western Ontario and McMaster Osteoarthritis Index, Harris Hip Score, Visual Analogue Scale and the EQ-5D Health Questionnaire. RESULTS: Seventy-two percent of patients who underwent conversion THA were treated with primary implants and never suffered from a major complication. PROMs were excellent for this group of patients. The distinction primary/conversion/revision THA could not explain differences in outcomes; however, the necessity of using revision implants and the development of major complications could. CONCLUSIONS: The majority of conversion total hip arthroplasties can be considered a primary replacement. Predicting outcomes for THA should focus on patient frailty and technical difficulties dealing with infection, stability and loss of bone stock and should discard the conversion versus revision terminology.

The comparison between total hip arthroplasty and hemiarthroplasty in patients with femoral neck fractures: a systematic review and meta-analysis based on 25 randomized controlled trials.

BACKGROUND: We performed an updated systematic review and meta-analysis which enrolled 25 prospective randomized controlled trials (RCTs) to compare the outcomes between total hip arthroplasty (THA) and hemiarthroplasty (HA) in patients with femoral neck fractures (FNFs). METHODS: We searched English databases which included PubMed, Embase (vis OvidSP), The Cochrane Library, and Web of Science, and Chinese databases Chinese National Knowledge Infrastructure (CNKI), VIP, Wang Fang, and China Biology Medicine Disc (CBM) in July 2020. The quality of each study was assessed according to the Cochrane Collaboration's Risk of Bias. Risk ratios (RRs) and weighted mean differences (WMDs) with 95% confidence intervals (95% CIs) were pooled with random-effects models. Data regarding baseline characteristics, hospital and surgery outcomes, clinical outcomes, patients' quality of life, common complications, prothesis-related complications, mortality, and costs were reported. RESULTS: A total of 25 RCTs involving 3223 patients (1568 THA and 1655 HA) were included. THA had longer hospital length (WMD = 0.721, P < 0.0001) and surgery time (WMD = 20.044, P < 0.0001), and more blood loss compared with HA (WMD = 69.109, P < 0.0001). THA showed better ratings in the Harris Hip Score during follow-up periods between 1 and 5 years while no differences within 6 months and after 9 years. THA was associated with higher quality-of-life EuroQol-5 Dimension (EQ-5D) scores after 2 years of surgery but no difference within 1 year. There was no difference in common complications. THA had significant higher rate of dislocation (WMD = 1.897, P = 0.002) and lower acetabular erosion (WMD = 0.030, P = 0.001). For mortality, there was no difference during all the follow-up periods except for slightly higher 2-year mortality after surgery. CONCLUSION: This meta-analysis demonstrates that THA has better medium-term functional results and quality of life and lower acetabular erosion rate, while HA shows better in reducing hospital stay, surgery time, and blood loss and also has lower dislocation rate.

Higher incidence of aseptic loosening caused by a lower canal filling ratio with a modified modular stem in total hip arthroplasty.

PURPOSE: Although a cementless modular prosthesis has shown reliable results, cases of unstable fixation and revision due to aseptic loosening were observed in our institute. The purpose of this study was to clarify the causes of unstable fixation of the prosthesis. METHODS: A total of 144 patients (154 hips) who underwent total hip arthroplasty using the modular prosthesis were retrospectively investigated. For the cohort study, 97 patients (104 hips) were included. The femoral component survival rate and sleeve fixation were assessed at a minimum follow-up of 5 years. Patients were divided into 2 groups, including stable and unstable fixation groups, by sleeve fixation. Clinical and radiographic outcomes were compared. RESULTS: The Kaplan-Meier survival rate at 9 years was 93% with revision for any reason as the endpoint in study cohort. The reasons for revision were recurrent dislocation (1 hip) and aseptic loosening of the stem (5 hips). A total of 88 hips (84.6%) showed stable fixation, and 16 hips (15.4%) showed unstable fixation at final follow-up. There was no significant difference in clinical outcomes between the 2 groups at final follow-up. The canal flare index was significantly higher, and the canal filling ratio was significantly lower in the unstable fixation group. CONCLUSION: Although the modified modular prosthesis was useful for treating anatomically difficult patients, we need to pay attention to both proximal/distal mismatch of the intramedullary canal and the canal filling ratio to achieve stable fixation and good long-term results.

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.

Dual mobility total hip arthroplasty in the treatment of femoral neck fractures.

AIMS: To evaluate the rate of dislocation following dual mobility total hip arthroplasty (DM-THA) in patients with displaced femoral neck fractures, and to compare rates of dislocation, surgical-site infection, reoperation, and one-year mortality between DM-THA and bipolar hemiarthroplasty (BHA). METHODS: Studies were selected based on the following criteria: 1) study design (retrospective cohort studies, prospective cohort studies, retrospective comparative studies, prospective comparative studies, and randomized controlled studies (RCTs)); 2) study population (patients with femoral neck fracture); 3) intervention (DM-THA or BHA); and 4) outcomes (complications during postoperative follow-up and clinical results). Pooled meta-analysis was carried out to evaluate the dislocation rate after DM-THA and to compare outcomes between DM-THA and BHA. RESULTS: A total of 17 studies (ten cohort studies on DM-THA and seven comparative studies of DM-THA and BHA) were selected. These studies included 2,793 patients (2,799 hips), made up of 2,263 DM-THA patients (2,269 hips) and 530 BHA patients (530 hips). In all, 16 studies were analyzed to evaluate dislocation rate after DM-THA. The cumulative dislocation rate was 4% (95% confidence interval (CI) 3 to 5). Seven studies were analyzed to compare the rates dislocation and surgical-site infection. The rate of dislocation was significantly lower in the DM-THA group than in the BHA group (risk ratio (RR) 0.3; 95% CI 0.17 to 0.53, p < 0.001, Z -4.11). There was no significant difference in the rate of surgical-site infection between the two groups (p = 0.580). Six studies reported all-cause reoperations. The rate of reoperation was significantly lower in the DM-THA group than in the BHA group (RR 0.5; 95% CI 0.32 to 0.78, p = 0.003, Z -3.01). Five studies reported one-year mortality. The mortality rate was significantly lower in the DM-THA group than in the BHA group (RR 0.58 95% CI 0.45 to 0.75, p < 0.0001, Z -4.2). CONCLUSION: While the evidence available consisted mainly of non-randomized studies, DM-THA appeared to be a viable option for patients with displaced fractures of the femoral neck, with better reported rates of dislocation, reoperation, and mortality than BHA. Cite this article: Bone Joint J 2020;102-B(11):1457-1466.

Straight stem and threaded cup in patients under 60 years of age: 28.8-30.2 years of follow-up.

PURPOSE: The aim of this retrospective observational study of one cohort was to evaluate the long-term outcome in patients younger than 60 years after total hip arthroplasty using a straight uncemented stem and an uncemented threaded cup. METHODS: Between 1986 and 1987, 75 hips of 75 patients (mean age, 53.35 ± 6.17 years) were consecutively implanted with an Alloclassic Zweymüller/Alloclassic SL stem and an Alloclassic CSF cup. Forty-four patients had died over the last 30 years. The remaining 31 patients (mean age, 82.9 ± 6.4 years) were reinvited for follow-up examinations. Clinical and radiographic evaluations were carried out. RESULTS: At a mean follow-up of 29.5 (28.8-30.2), 4 patients (5.3%) were lost to follow-up. For the endpoint aseptic loosening (defined as the removal of stem or the cup for 2 cases), the overall survival rate is 97.3%. For the endpoint revision for any reason (22 patients), the survival rate is 70.6%. Eleven patients needed an exchange of head and liner, caused by wear. The average time from implantation until change of head and liner was 21.44 years (SD 5.92). Other reasons for revision surgery were septic loosening (3 cases), aseptic loosening of stem and cup (1 case), aseptic loosening of stem (1 case), periprosthetic calcification (2 cases), implant fracture (1 case), periprosthetic fracture (1 case), intraoperative fissure of stem (1 case), and total wear of liner including cup (1 case). CONCLUSION: The combination of a straight stem (Alloclassic) and a screw cup (CSF) shows excellent results in young patients under the age of 60 at ultra-long-term follow-up at 30 years. Revisions due to wear of the polyethylene liner are more likely than in the older patients.