Clinical Outcomes, Health Care Costs and Prognostic Factors for Total Knee Arthroplasty: A Multilevel Analysis of a National Cohort Study Using Administrative Claims Data

No effect of fixation type on early and late mortality after total knee arthroplasty: a Dutch arthroplasty register study

PURPOSE

Postoperative mortality is commonly reported as outcome measurement after total knee arthroplasty (TKA). Mortality might be influenced by multiple factors including cementation of the prosthesis. Until now, the influence of cementation on early and late mortality after TKA is unknown. The aim of the present study was to determine the effect of fixation on early and late mortality after primary TKA.

METHODS

All patients in the Dutch Arthroplasty Register (LROI) with a primary TKA for osteoarthritis were eligible for inclusion. Data collected from 2007 to 2014 with follow-up until January 2020 were used. Survival analysis was performed by using Kaplan-Meier and Cox survival analysis to determine the mortality rate according to fixation. Adjustments were made for age at time of surgery, gender, American Society of Anaesthesiologists class, and year of surgery.

RESULTS

In total 108,687 TKA were included for analysis, which comprised 95,857 cemented, 6,140 cementless and 6,690 hybrid TKA. The early and late mortality rate in cemented TKA was statistically not different compared to cementless or hybrid TKA at 30 days, 31-90 days, 91 days-1 year and 1-5 years. The hazard ratio at 30 days was 1.05 (CI 0.49-2.25) for hybrid fixation, and 1.46 (CI 0.74-2.90) for cementless fixation compared to cemented fixation. The 1-5 years hazard ratio was 1.06 (CI 0.96-1.17) and 0.97 (CI 0.87-1.08), respectively.

CONCLUSION

Based on register data, method of fixation does not influence early mortality after primary TKA. This suggests that there is no preferred fixation technique for primary TKA based on the mortality rates.

LEVEL OF EVIDENCE

IV.

Prognostic Factors of Clinical and Economic Outcomes of Hip Arthroplasty in a Developing Country: A Multilevel Analysis with a 4-Year Cohort Study

INTRODUCTION

This study is aimed at estimating the 30-day postoperative mortality rate and total costs of the medical episode, as well as determining prognostic factors associated with these outcomes for adult patients who have undergone total hip arthroplasty (THA) in Colombia's contributory health system.

METHODS

This was a retrospective cohort using administrative data and included adult patients enrolled in Colombia's contributory health system who underwent THA between the years 2011 and 2014. Outcomes were 30-day mortality ICU admissions, and the 1-year rate of fractures and revisions as well as the total cost of the medical episode incurred by the third-payer for 90 days following the procedure. Multilevel linear regression models were also generated to determine the prognostic factors associated with the outcomes presented.

RESULTS

The study included 17,289 patients, with an average age of 67 years. Outcome rates were calculated per 100 surgeries, resulting in 2.15 for mortality, 3.41 for ICU admissions, 2.42 for revision hip arthroplasty and 0.62 for periprosthetic fractures. This study found the age and Charlson Comorbidity Index were associated with mortality and complications, and that being female and performing the procedure in the capital city were protective factors. It also found that the median total cost of the medical episode was USD $ USD$2742.161 (p25-p75: 353.092-3291.747). The multivariate model found increasing trends in cost as age and CCI scores rose, and higher costs in the Atlantic region.

CONCLUSIONS

Colombia has higher rates of complications from THA than other countries but lower health system costs. For these patients, age, CCI and the geographic region are factors that are associated with mortality, complications, and health system costs.

Factors Affecting 30-Day Mortality following Primary Elective Total Knee Arthroplasty: A Database Study of 326,157 Patients

Despite its rarity, the risk of mortality following primary elective total knee arthroplasty (TKA) is a critical component of surgical decision-making and patient counseling. The purpose of our study was to (1) determine the overall 30-day mortality rate for unilateral primary elective TKA patients, (2) determine the 30-day mortality rates when stratified by age, comorbidities, and preoperative diagnosis, and (3) identify the distribution of (i) patient demographics, (ii) baseline comorbidities, and (iii) preoperative diagnoses between mortality and mortality-free cohorts. A total of 326,157 patients underwent primary elective TKA (2011-2018) were identified through retrospective review of the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Patients were divided into 30-day mortality (n = 320) and mortality-free (n = 325,837) cohorts. Patient demographics, preoperative comorbidities, and preoperative diagnoses were compared. Age group, American Society of Anesthesiology (ASA) score, and modified Charlson Comorbidity Index (CCI) scores were normalized per 1000 and stratified by preoperative diagnosis. The overall mortality rate was 0.098%. Older age (p < 0.001) and male gender (p < 0.001) were associated with increased mortality. There was no association between mortality and race (p = 0.346) or body mass index (BMI) class (p = 0.722). All reported comorbidities except smoking status were significantly greater in the mortality cohort (p < 0.05). For ASA scores of I, II, III, and IV, the number of deaths per 1,000 were 0.16, 0.47, 1.4, and 4.4, respectively. For CCI scores of 0, 1, 2, 3, 4, and 6, mortality rates per 1,000 were 0.76, 2.1, 7.0, 11, 29, and 7.6, respectively. Mortality rates for a preoperative diagnosis of osteoarthritis (OA) versus non-OA were, respectively, 0.096% and 0.19% (p < 0.001). Increased age, male gender, increased comorbidity burden, and non-OA preoperative diagnoses are associated with higher rates of 30-day postoperative mortality. There were no significant associations between BMI or race and 30-day mortality. These findings aid in identifying of higher-risk patients, who can then receive appropriate counseling or preoperative interventions to reduce the risk of perioperative mortality.

Patient-Related Risk Factors for Unplanned 30-Day Hospital Readmission Following Primary and Revision Total Knee Arthroplasty: A Systematic Review and Meta-Analysis

Total knee arthroplasty (TKA) is a highly effective procedure for advanced osteoarthritis of the knee. Thirty-day hospital readmission is an adverse outcome related to complications, which can be mitigated by identifying associated risk factors. We aimed to identify patient-related characteristics associated with unplanned 30-day readmission following TKA, and to determine the effect size of the association between these risk factors and unplanned 30-day readmission. We searched MEDLINE and EMBASE from inception to 8 September 2020 for English language articles. Reference lists of included articles were searched for additional literature. Patients of interest were TKA recipients (primary and revision) compared for 30-day readmission to any institution, due to any cause, based on patient risk factors; case series were excluded. Two reviewers independently extracted data and carried out critical appraisal. In-hospital complications during the index admission were the strongest risk factors for 30-day readmission in both primary and revision TKA patients, suggesting discharge planning to include closer post-discharge monitoring to prevent avoidable readmission may be warranted. Further research could determine whether closer monitoring post-discharge would prevent unplanned but avoidable readmissions. Increased comorbidity burden correlated with increased risk, as did specific comorbidities. Body mass index was not strongly correlated with readmission risk. Demographic risk factors included low socioeconomic status, but the impact of age on readmission risk was less clear. These risk factors can also be included in predictive models for 30-day readmission in TKA patients to identify high-risk patients as part of risk reduction programs.