All-Cause Versus Complication-Specific Readmission Following Total Knee Arthroplasty

Measurement of periarticular subcutaneous fat on CT images and adverse outcomes following total knee arthroplasty

Background

Obesity is associated with a higher rate of wound complications following primary total knee arthroplasty (TKA). With readily available computer tomography (CT) images from robotic-assisted TKA, we analyzed measurement of fat content on preoperative CT images as a possible predictor of wound complications following primary TKA.

Methods

Patients who underwent robotic-assisted TKA at one institution in 2018 were included in this retrospective cohort study. Two independent reviewers measured three SCF areas at different axial CT cuts and normalized them by dividing the area of the distal femur. These areas were distributed into 4 groups. Any wound complication that required clinical or surgical intervention was reviewed and analyzed. For further comparison, prepatellar SCF thickness ratio measured on CT scan and BMI were grouped and analyzed similarly for wound complications. We also analyzed any association of SCF measurement with secondary outcomes such as operative time, length of stay, readmission, and reoperation.

Results

One hundred fifty patients with diagnosis of osteoarthritis, mean age of 64 years and BMI of 34.3 kg/m2 were included in this study. Ninety-one patients (61 %) were female. Normalized SCF measurements at 2 cm above the patella, mid-patella, and tibial tubercle had excellent intraclass correlation coefficient at 0.987, 0.989, and 0.989, respectively. When SCF at 2 cm above patella was analyzed, Group 1 (smallest amount of SCF) had a significantly higher wound complication rate compared with Groups 2 and 3 combined (18.9 vs 5.3 %, p = 0.036). Group 4 (largest amount of SCF) also had a significantly higher wound complication rate compared with Groups 2 and 3 combined (18.9 vs 5.3 %, p = 0.036).

Conclusions

Accurate and consistent measurement of periarticular fat around the knee based on axial CT images demonstrated that moderate amount of fat is associated with better clinical outcomes following primary TKA. Our study did not find any clinical significance of gender difference in fat distribution. Therefore, more studies should be undertaken to evaluate for any clinical association of gender-specific fat distribution and to confirm our finding that a certain amount of fatty tissue is necessary for improved outcomes following TKA.

Platelet-rich plasma relieves inflammation and pain by regulating M1/M2 macrophage polarization in knee osteoarthritis rats

Knee osteoarthritis (KOA) is a common, chronic, degenerative disease. Platelet-rich plasma (PRP) can significantly relieve KOA pain; however, the mechanism of PRP-induced analgesia remains to be studied. Macrophages are closely related to KOA pain, and regulating macrophage polarization may be an effective way to relieve KOA pain. Therefore, the aim of this study is: First, to explore whether PRP can effectively relieve pain in a KOA animal model and whether it relieves pain by regulating macrophage polarization. Second, to explore the mechanism by which PRP regulates macrophage polarization. Thirty-six healthy male SD rats were randomly divided into sham group, MIA group and PRP group. The KOA rat model was established by injecting 1 mg of MIA into the joint cavity. Behavioral tests, including weight-bearing asymmetry, hot plate, and von Frey hairs tests, were performed. The positive expression rates of inducible nitric oxide synthase (iNOS) and CD163 in the synovium were detected via immunohistochemical staining. Meanwhile, RAW 264.7 cells induced by lipopolysaccharide were treated with PRP in vitro. The production levels of the nuclear factor kappa-B (NF-κB) pathway-related proteins NF-κB p65, inhibitor-κ binding protein α (IκBα), p-NF-κB p65, p-IκBα and the iNOS and CD163 proteins were measured via western blotting. An enzyme-linked immunosorbent assay was used to detect the release of tumor necrosis factor-α (TNF-α), interleukin-1 beta (IL-1β), interleukin-10 (IL-10), and nerve growth factor (NGF). The behavioral results revealed that PRP relieved pain. PRP reduced the proportion of M1/M2 macrophages among synovial macrophages, significantly inhibited the secretion of TNF-α and IL-1β in the synovium, and increased the secretion of IL-10. In addition, in vivo experiments revealed that PRP decreased the protein expression of iNOS, p-IκBα/IκBα, and p-p65/p65 and increased the protein expression of CD163. Furthermore, PRP decreased TNF-α, IL-1β, and NGF levels in RAW 264.7 cells and increased the secretion of IL-10. Our findings indicate that PRP can improve long-term relief from KOA pain. The analgesic mechanism promotes the transformation of M1 macrophages to M2 macrophages by inhibiting the NF-κB signaling pathway, which reduces the release of downstream pain-causing factors, thus relieving inflammation and pain.

Distinct Care Needs and Episodes of Care: Comparing Medical versus Orthopaedic Readmissions after Elective Primary Total Knee Arthroplasty

Hospital readmissions after primary total knee arthroplasty (TKA) significantly drive health care expenditure and resource utilization. Recent studies have suggested differences between medical and orthopaedic readmissions after TKA and their episodes of care (EOCs) but lack patient-level data reporting. This study aimed to compare EOCs for medical and orthopaedic-related readmissions regarding initial readmission wards, services consulted, intensive care unit (ICU) admissions, blood transfusions, surgical interventions, length of stay, and discharge disposition.All patients enrolled in a prospective data collection system at a tertiary medical center undergoing elective, unilateral, primary TKA from 2016 to 2020 and readmitted within 90 days of discharge were included. Readmissions were categorized as related to medical or orthopaedic causes. Patients' electronic medical records were reviewed to collect demographic and clinical information about EOC associated with the readmission hospital course.In total, 82.4% (580/704) of 90-day readmissions after elective, primary TKA were related to medical causes, with the remaining 17.6% (124/704) of readmissions due to orthopaedic causes. Medical readmissions most often pertained to gastrointestinal complaints, while wound complications accounted for most orthopaedic readmissions. Most readmissions (63.1%, 444/704) occurred within the first 30 days after TKA. Patients with medical and orthopaedic readmissions had differences in EOC, such that more medical readmissions required ICU care (10.6 vs. 1.6%, p < 0.001), and more patients with orthopaedic readmissions needed a surgical intervention (65.4 vs. 6.7%, p < 0.001).By understanding differences in EOC for medical and orthopaedic readmissions after TKA, targeted initiatives can be developed to deliver more efficient, cost-effective orthopaedic surgical care, as the orthopaedic surgical community continues to provide value-based care.

Predicting 30-day readmissions in pneumonia patients using machine learning and residential greenness

Introduction

Identifying factors that increase the risk of hospital readmission will help determine high-risk patients and decrease the socioeconomic burden. Pneumonia is associated with high readmission rates. Although residential greenness has been reported to have beneficial health effects, no studies have investigated its importance in predicting readmission in patients with pneumonia. This study aimed to build prediction models for 30-day readmission in patients with pneumonia and to analyze the importance of risk factors for readmission, mainly residential greenness.

Methods

Data on 47 risk factors were collected from 22,600 patients diagnosed with pneumonia. Residential greenness was quantified as the mean of normalized difference vegetation index of the district in which the patient resides. Prediction models were built using logistic regression, support vector machine, random forest, and extreme gradient boosting.

Results

Residential greenness was selected from the top 21 risk factors after feature selection. The area under the curves of the four models were 0.6919, 0.6931, 0.7117, and 0.7044. Age, red blood cell distribution width, and history of cancer were the top three risk factors affecting readmission prediction. Residential greenness was the 15th important factor.

Discussion

We constructed prediction models for 30-day readmission of patients with pneumonia by incorporating residential greenness as a risk factor. The models demonstrated sufficient performance, and residential greenness was significant in predicting readmission. Incorporating residential greenness into the identification of groups at high risk for readmission can complement the possible loss of information when using data from electronic health records.

The role of subcutaneous fat and BMI in predicting surgical outcomes and patient reported outcomes in robotic-assisted total hip arthroplasty

Background

The purpose of this study was to assess if subcutaneous fat (SCF) or BMI is a predictor of surgical complications and patient reported outcomes in patients undergoing robotic-assisted total hip arthroplasty (THA).

Methods

Patients who underwent robotic-assisted primary THAs at one institution between 2018 and 2020 were included in this retrospective cohort study. Prior to surgery, computed tomography (CT) was used to measure SCF in the posterolateral quadrant of the hip. SCF was measured 3 centimeters (cm) proximal to the greater trochanter (PGT) and 3 cm inferior to the distal tip of the greater trochanter (DGT).Measurements were normalized to the size of the patient's bony anatomy by dividing the subcutaneous fat area measurement by the transverse diameter of the femur 10 cm inferior to the tip of the greater trochanter. Patients were divided into quintiles determined by SCF distribution around the mean (groups 1-5) and BMI (BMI<25, BMI 25-29.9, BMI 30-34.9, BMI 35-39.9, and >40). Ninety day outcomes and PROMIS (Patient Reported Outcome Measures Information System) scores were acquired from the Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI) database preoperatively, at 14-112 days post-operative and at the latest follow up.

Results

There were 175 patients identified with a mean age of 63.83 years (range 27-89) and a mean BMI of 30.73kg/m2 (range 18.2-48.4). Interclass correlation coefficient was greater than 0.9 in all PGT, DGT, and GT measurements. Analysis of Variance (ANOVA) found there was a significantly shorter time from incision to closure in quintiles 1 and 3 when compared to the SCF quintile 5 (p<0.05) and that there was a significantly shorter time from incision to closure in BMI categories 1, 2, and 3 when compared to BMI category 5 (BMI > 40). There were no differences between SCF and BMI as predictive of length of stay, transfusion status, infection, or PROMIS scores.

Conclusion

It can be concluded that hip SCF on axial CT images can reliably measure SCF and is predictive of time from incision to closure, but it does not show a significant difference in predicting the length of stay, infection, or PROMIS scores when compared to BMI.

Racial and Ethnic Disparities in Primary Total Knee Arthroplasty Outcomes: A Systematic Review and Meta-Analysis of Two Decades of Research

Racial disparities in outcomes following total knee arthroplasty (TKA) remain persistent. This systematic review and meta-analysis aims to comprehensively synthesize data between 2000-2020. An electronic search of studies was performed on PubMed, SCOPUS, and the Cochrane Library databases from January 1, 2000, and December 31, 2020. Random effects models were used to report unadjusted and adjusted estimates for a comprehensive list of care outcomes in TKA. 63 studies met PRISMA criteria. Black patients report greater odds of in-hospital mortality (odds ratio [OR]: 1.37, 95% CI: 1.00-1.59 (p = 0.049); adjusted OR [aOR]: 1.34, 95% CI: 1.09-1.64), in-hospital complications (OR: 1.31, 95% CI: 1.27-1.35), 30-day complications (aOR: 1.19, 95% CI: 1.07-1.33), infection (OR: 1.11, 95% CI: 1.07-1.16; aOR: 1.30, 95% CI: 1.16-1.46), bleeding (OR: 1.33, 95% CI: 1.03-1.71; aOR: 1.47, 95% CI: 1.23-1.75), peripheral vascular events (PVE) (aOR: 1.46, 95% CI: 1.11-1.92), length of stay (LOS) (OR: 1.20, 95% CI: 1.08-1.34), extended-LOS (aOR: 1.89, 95% CI: 1.53-2.33), discharge disposition (OR: 1.59, 95% CI: 1.29-1.96; aOR: 1.96, 95% CI: 1.70-2.25), 30-day (OR: 1.20, 95% CI: 1.13-1.27; aOR: 1.17 95% CI: 1.09-1.26) and 90-day (OR: 1.46, 95% CI: 1.17-1.82) readmission compared to White patients. Disparities in bleeding, extended-LOS, discharge disposition, PVE, and 30-day readmission were observed in Asian patients. Hispanic patients experienced disparities in extended LOS and discharge disposition, while Native-American patients had disparities in bleeding outcomes. Persistent racial disparities in TKA outcomes highlight a need for standardized outcome measures and comprehensive data collection across multiple racial groups to ensure greater healthy equity.

Readmission rate and early complications in patients undergoing total knee arthroplasty: A retrospective study

BACKGROUND

Total knee arthroplasty (TKA) can improve pain, quality of life, and functional outcomes. Although uncommon, postoperative complications are extremely consequential and thus must be carefully tracked and communicated to patients to assist their decision-making before surgery. Identification of the risk factors for complications and readmissions after TKA, taking into account common causes, temporal trends, and risk variables that can be changed or left unmodified, will benefit this process.

AIM

To assess readmission rates, early complications and their causes after TKA at 30 days and 90 days post-surgery.

METHODS

This was a prospective and retrospective study of 633 patients who underwent TKA at our hospital between January 1, 2017, and February 28, 2022. Of the 633 patients, 28 were not contactable, leaving 609 who met the inclusion criteria. Both inpatient and outpatient hospital records were retrieved, and observations were noted in the data collection forms.

RESULTS

Following TKA, the 30-day and 90-day readmission rates were determined to be 1.1% (n = 7) and 1.8% (n = 11), respectively. The unplanned visit rate at 30 days following TKA was 2.6% (n = 16) and at 90 days was 4.6% (n = 28). At 90 days, the unplanned readmission rate was 1.4% (n = 9). Reasons for readmissions included medical (27.2%, n = 3) and surgical (72.7%, n = 8). Unplanned readmissions and visits within 90 days of follow-up did not substantially differ by age group (P = 0.922), body mass index (BMI) (P = 0.633), unilateral vs bilateral TKA (P = 0.696), or patient comorbidity status (30-day P = 0.171 and 90-day P = 0.813). Reoperation rates after TKA were 0.66% (n = 4) at 30 days and 1.15% (n = 8) at 90 days. The average length of stay was 6.53 days.

CONCLUSION

In this study, there was a low readmission rate following TKA. There was no significant correlation between readmission rate and patient factors such as age, BMI, and co-morbidity status.

Mid-term outcomes of a kinematically designed cruciate retaining total knee arthroplasty

BACKGROUND

Advances in implant material and design have allowed for improvements in total knee arthroplasty (TKA) outcomes. A cruciate retaining (CR) TKA provides the least constraint of TKA designs by preserving the native posterior cruciate ligament. Limited research exists that has examined clinical outcomes or patient reported outcome measures (PROMs) of a large cohort of patients undergoing a CR TKA utilizing a kinematically designed implant. It was hypothesized that the studied CR Knee System would demonstrate favorable outcomes and a clinically significant improvement in pain and functional scores.

AIM

To assess both short-term and mid-term clinical outcomes and PROMs of a novel CR TKA design.

METHODS

A retrospective, multi-surgeon study identified 255 knees undergoing a TKA utilizing a kinematically designed CR Knee System (JOURNEY™ II CR; Smith and Nephew, Inc., Memphis, TN) at an urban, academic medical institution between March 2015 and July 2021 with a minimum of two-years of clinical follow-up with an orthopedic surgeon. Patient demographics, surgical information, clinical outcomes, and PROMs data were collected via query of electronic medical records. The PROMs collected in the present study included the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) and Patient-Reported Outcomes Measurement Information System (PROMIS®) scores. The significance of improvements in mean PROM scores from preoperative scores to scores collected at six months and two-years postoperatively was analyzed using Independent Samples t-tests.

RESULTS

Of the 255 patients, 65.5% were female, 43.8% were White, and patients had an average age of 60.6 years. Primary osteoarthritis (96.9%) was the most common primary diagnosis. The mean surgical time was 105.3 minutes and mean length of stay was 2.1 d with most patients discharged home (92.5%). There were 18 emergency department (ED) visits within 90 d of surgery resulting in a 90 d ED visit rate of 7.1%, including a 2.4% orthopedic-related ED visit rate and a 4.7% non-orthopedic-related ED visit rate. There were three (1.2%) hospital readmissions within 90 d postoperatively. With a mean time to latest follow-up of 3.3 years, four patients (1.6%) required revision, two for arthrofibrosis, one for aseptic femoral loosening, and one for peri-prosthetic joint infection. There were significant improvements in KOOS JR, PROMIS Pain Intensity, PROMIS Pain Interference, PROMIS Mobility, and PROMIS Physical Health from preoperative scores to six month and two-year postoperative scores.

CONCLUSION

The evaluated implant is an effective, novel design offering excellent outcomes and low complication rates. At a mean follow up of 3.3 years, four patients required revisions, three aseptic and one septic, resulting in an overall implant survival rate of 98.4% and an aseptic survival rate of 98.8%. The results of our study demonstrate the utility of this kinematically designed implant in the setting of primary TKA.

Trends and risk factors for readmissions following press-fit total knee arthroplasty for the treatment of end-stage osteoarthritis of the knee: a five-year analysis

INTRODUCTION

The development of new prostheses with improved osseointegration, bone preservation, and reduced cost has renewed interest in uncemented total knee arthroplasty (UCTKA). In the current study, we aimed to: (1) assess demographic data of patients who were and were not readmitted and (2) identify patient-specific risk factors associated with readmission.

METHODS

A retrospective query from the PearlDiver database was performed from January 1, 2015, to October 31, 2020. International Classification of Disease, Ninth Revision (ICD-9), ICD-10, or Current Procedural Terminology (CPT) coding was used to distinguish cohorts of patients who had osteoarthritis of the knee and underwent UCTKA. Patients readmitted within 90 days were classified as the study population, while those who were not readmitted were classified as control. A linear regression model was utilized to analyze readmission risk factors.

RESULTS

The query yielded 14,575 patients, with 986 (6.8%) being readmitted. Patient demographics such as age (P < 0.0001), sex (P < 0.009), and comorbidity (P < 0.0001) were associated with annual 90-day readmission. Patient-specific risk factors associated with 90-day readmission following press-fit total knee arthroplasty were: arrhythmia (OR: 1.29, 95% CI: 1.11-1.49, P < 0.0005), coagulopathy (OR: 1.36, 95% CI: 1.13-1.63, P < 0.0007), fluid and electrolyte abnormalities (OR: 1.59, 95% CI: 1.38-1.84, P < 0.0001), iron deficiency anemia (OR: 1.49, 95% CI: 1.27-1.73, P < 0.0001), and obesity (OR: 1.37, 95% CI: 1.18-1.60, P < 0.0001).

DISCUSSION

This study demonstrates that patients with comorbidities, such as fluid and electrolyte problems, iron deficiency anemia, and obesity, were at an increased risk of readmission after having an uncemented total knee replacement. The risks of readmission following an uncemented total knee arthroplasty can be discussed with patients who have certain comorbidities by arthroplasty surgeons.

Risk factors for rehospitalization within 90 days in patients with total joint replacement: A meta-analysis

BACKGROUND

The risk factors influencing the readmission within 90 days following total joint replacement (TJR) are complex and heterogeneous, and few systematic reviews to date have focused on this issue.

METHODS

Web of Science, Embase, PubMed, and Chinese National Knowledge Infrastructure databases were searched from the inception dates to December 2022. Relevant, published studies were identified using the following keywords: risk factors, rehospitalization, total hip replacement, total knee replacement, total shoulder replacement, and total joint replacement. All relevant data were collected from the studies that meet the inclusion criteria. The methodological quality of the studies was assessed using the Newcastle-Ottawa Scale (NOS).

RESULTS

Of 68,336 patients who underwent TJR, 1,269,415 (5.4%) were readmitted within 90 days. High American Society of Anesthesiologists (ASA) class (OR, 1.502; 95%CI:1.405-1.605; P < .001), heart failure (OR,1.494; 95%CI: 1.235-1.754; P < .001), diabetes (OR, 1.246; 95%CI:1.128-1.377; P < .001), liver disease (OR, 1.339; 95%CI:1.237-1.450; P < .001), drinking (OR, 1.114; 95%CI:1.041-1.192; P = .002), depression (OR, 1.294; 95%CI:1.223-1.396; P < .001), urinary tract infection (OR, 5.879; 95%CI: 5.119-6.753; P < .001), and deep vein thrombosis (OR, 10.007; 95%CI: 8.787-11.396; P < .001) showed statistically positive correlation with increased 90-day readmissions after TJR, but high blood pressure, smoking, and pneumonia had no significant association with readmission risk.

CONCLUSION

The findings of this review and meta-analysis will aid clinicians as they seek to understand the risk factors for 90-day readmission following TJR. Clinicians should consider the identified key risk factors associated with unplanned readmissions and develop strategies to risk-stratify patients and provide dedicated interventions to reduce the rates of readmission and enhance the recovery process.

Severe Obesity Is an Independent Risk Factor of Early Readmission and Nonhome Discharge After Cervical Disc Replacement

OBJECTIVE

Despite growing interest in cervical disc replacement (CDR) for conditions such as cervical radiculopathy, limited data exists describing the impact of obesity on early postoperative outcomes and complications. These data are especially important as nearly half of the adult population in the United States is expected to become obese (body mass index [BMI] ≥ 30 kg/m2) by 2030. The goal of this study was to compare the demographics, perioperative variables, and complication rates following CDR.

METHODS

The 2005-2020 American College of Surgeons National Surgical Quality Improvement Program datasets were queried for patients who underwent primary 1- or 2-level CDR. Patients were divided into 3 cohorts: Nonobese (BMI: 18.5-29.9 kg/m2), Obese class-I (BMI: 30-34.9 kg/m2), Obese class-II/III (BMI ≥ 35 kg/m2). Morbidity was defined as the presence of any complication within 30 days postoperatively. Rates of 30-day readmission, reoperation, morbidity, individual complications, length of stay, frequency of nonhome discharge disposition were collected.

RESULTS

A total of 5,397 patients were included for analysis: 3,130 were nonobese, 1,348 were obese class I, and 919 were obese class II/III. There were more 2-level CDRs performed in the class II/III cohort compared to the nonobese group (25.7% vs. 21.5%, respectively; p < 0.05). Class-II/III had more nonhome discharges than class I and nonobese (2.1% vs. 0.5% vs. 0.7%, respectively; p < 0.001). Readmission rates differed as well (nonobese: 0.5%, class I: 1.1%, class II/III: 2.1%; p < 0.001) with pairwise significance between class II/II and nonobese. Class II/III obesity was an independent risk factor for both readmission (odds ratio [OR], 3.32; p = 0.002) and nonhome discharge (OR, 2.51; p = 0.02). Neither 30-day reoperation nor morbidity rates demonstrated significance. No mortalities were reported.

CONCLUSION

Although obese class-II/III were risk factors for 30-day readmission and nonhome discharge, there was no significant difference in reoperation rates or morbidity. CDR procedures can continue to be safely preformed independent of obesity status.

Hospital Readmissions After Total Joint Arthroplasty: An Updated Analysis and Implications for Value-Based Care

BACKGROUND

While risk factors have been published for readmissions following primary total joint arthroplasty, little is known about the etiology of those costly adverse events. In this study, we sought to identify the reasons for 30-day readmission following primary total joint arthroplasty in a contemporary national patient sample.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program was queried to identify 367,199 patients who underwent primary total knee (TKA) or hip arthroplasty (THA) between 2011 and 2018. The primary outcomes were the annual rates of 30-day readmissions and the causes of those readmissions.

RESULTS

The 30-day readmission rate trended downward from 4.5% in 2011 to 3.3% in 2018. Medical complications accounted for 52.6% and 38.5% of readmissions following TKA and THA, respectively. Diseases of the circulatory system, abnormal laboratory values, and diseases of the digestive system were the leading causes of medical readmissions. Surgical complications accounted for 37.7% and 50.7% of readmissions following TKA and THA, respectively. Surgical site infections/wound disruption and venous thromboembolism were the leading two causes of surgical readmissions for THA and TKA. Prosthetic complications-namely dislocations and periprosthetic fractures-were the third leading cause of surgical readmissions for THA. For TKA, musculoskeletal conditions-namely pain and hematoma-were the third leading cause of surgical readmissions.

CONCLUSION

Medical complications accounted for half of all TKA readmissions and more than a third of THA readmissions. This could penalize institutions participating in value-based payment programs or dissuade others who are considering participation in such programs.

Robotic-assisted TKA reduces surgery duration, length of stay and 90-day complication rate of complex TKA to the level of noncomplex TKA

INTRODUCTION

Complex primary total knee arthroplasties (TKA) are reported to be associated with excessive episode of care (EOC) costs as compared to noncomplex procedures. The impact of robotic assistance (rTKA) on economic outcome parameters in greater case complexity has not been described yet. The purpose of this study was to investigate economic outcome parameters in the 90-days postoperative EOC in robotic-assisted complex versus noncomplex procedures.

MATERIALS AND METHODS

This study is a retrospective, single-center review of 341 primary rTKAs performed between 2017 and 2020. Patient collective was stratified into complex (n = 218) and noncomplex TKA (n = 123) based on the presence of the following criteria: Obese BMI, coronal malalignment, flexion contracture > 10°, posttraumatic status, previous correction osteotomy, presence of hardware requiring removal during surgery, severe rheumatoid arthritis. Group comparison included surgery duration, length of stay (LOS), surgical site complications, readmissions, and revision procedures in the 90-days EOC following rTKA.

RESULTS

The mean surgery duration was marginally longer in complex rTKA, but showed no significant difference (75.26 vs. 72.24 min, p = 0.258), neither did the mean LOS, which was 8 days in both groups (p = 0.605). No differences between complex and noncomplex procedures were observed regarding 90-days complication rates (7.34 vs. 4.07%, p = 0.227), readmission rates (3.67 vs. 3.25%, p = 0.841), and revision rates (2.29 vs. 0.81%, p = 0.318).

CONCLUSIONS

Robotic-assisted primary TKA reduces the surgical time, inpatient length of stay as well as 90-days complication and readmission rates of complex TKA to the level of noncomplex TKA. Greater case complexity does not seem to have a negative impact on economic outcome parameters when surgery is performed with robotic assistance.

Incidence, patterns and risk factors for readmission following knee arthroplasty in China: A national retrospective cohort study

BACKGROUND

Limited data exist on readmission following knee arthroplasty (KA) in countries without well-established referral or extended care systems. This study aimed to investigate the incidence, patterns and risk factors for readmission following KA in China.

MATERIAL AND METHODS

In this national retrospective cohort study, we reviewed 167,265 primary KAs registered in the Hospital Quality Monitoring System in China between 2013 and 2018. Readmissions after KA within 30 and 90 days were evaluated. The causes for readmission were identified and classified as surgical or medical. The potential risk factors of readmission were assessed using multivariable logistic regression.

RESULTS

4017 (2.4%) patients readmitted within 30 days, and 7258 (4.3%) patients readmitted within 90 days. The readmission rate exhibited a downward trend during the period from 2013 to 2018 (2.7%-2.3% for 30-day readmission; 4.5%-4.2% for 90-day readmission). Surgical causes contributed to 54.3% readmissions within 30 days and 47.3% readmissions within 90 days. Wound infection/complication, joint pain, and thromboembolism were the most frequently reported reasons for surgical readmission. Older age, male sex, single marital status, non-osteoarthritis indication, a high comorbidity index, non-provincial hospitals, low hospital volume, and longer length of stay were associated with an increased risk of readmission. The geographic regions of hospitals contributed greatly to the variety of readmissions.

CONCLUSION

The readmission rate following KA decreased from 2013 to 2018. Surgery-related causes, especially wound infection/complication and pain, accounted for a large proportion. Both patient and hospital factors were associated with readmissions. Improved primary care and targeted measures are needed to help further prevent readmissions and optimize resource utilization.

Revisiting Short-term Outcomes of Conventional and Computer-Assisted Total Knee Arthroplasty: A Population-based Study

Background:

Population-based studies showing the advantage of computer-assisted total knee arthroplasty (CATKA) over conventional total knee arthroplasty (TKA) are outdated. More recent institution-based studies with relatively small sample sizes may hinder wider adoption. This cohort-based study aimed to compare postoperative CATKA and TKA in-hospital complications and 90-day all-cause readmissions using 2017-2018 data.

Methods:

Patients who underwent a primary unilateral CATKA or TKA were identified in the New York Statewide Planning and Research Cooperative System database. In-hospital complications were defined based on the 2020 Centers for Medicare & Medicaid Services total hip arthroplasty and TKA complications measure. Ninety-day readmissions were identified using unique patient identifiers. Logistic regression with a generalized estimating equation was used to assess associations of computer assistance with in-hospital complications and 90-day all-cause readmissions.

Results:

A total of 80,468 TKAs were identified during the study period, of which 7,395 (9.2%) were CATKAs. Significantly fewer complications occurred among patients who had CATKAs compared with conventional TKAs (0.4% of total CATKAs vs 2.6% of total conventional TKAs, P < 0.001); patients who had CATKAs had fewer 90-day all-cause readmissions compared with those who underwent TKAs (363 vs 4,169 revisits, P < 0.01). Computer assistance was associated with significantly lower odds of in-hospital complications (odds ratio, 0.15, 95% confidence interval, 0.09 to 0.24; P < 0.05) but not 90-day all-cause readmissions.

Conclusion:

Patients undergoing CATKAs had markedly lower odds of in-hospital complications, compared with patients having TKAs, which has implications for both patient outcomes and hospital reimbursement. These more recent cohort-based findings encourage wider CATKA adoption.

Synovial tissue-derived extracellular vesicles induce chondrocyte inflammation and degradation via NF-κB signalling pathway: An in vitro study

Osteoarthritis (OA) is a whole-joint disease characterized by synovial inflammation and cartilage degeneration. However, the relationship between synovial inflammation and cartilage degeneration remains unclear. The modified Hulth's method was adopted to establish a knee OA (KOA) rabbit model. Synovial tissue was collected after 8 weeks, and synovial tissue-derived extracellular vesicles (ST-EVs) were extracted by filtration combined with size exclusion chromatography (SECF), followed by identification through transmission electron microscopy (TEM), nanoparticle tracer analysis (NTA) and Western blot (WB). The collagenase digestion method was used to extract normal rabbit chondrocytes, which were then treated with the SF-EVs to observe the effect and mechanism of SF-EVs on chondrocytes. The morphology, particle size and labelled protein marker detection confirmed that SECF successfully extract ST-EVs. The ST-EVs in the KOA state significantly inhibited chondrocyte proliferation and promoted chondrocytes apoptosis. Moreover, the ST-EVs also promoted the expression of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α and COX-2) and cartilage degradation-related enzymes (MMP13, MMP9 and ADAMTS5) in the chondrocytes. Mechanistically, the ST-EVs significantly promoted the activation of NF-κB signalling pathway in chondrocytes. Inhibition the activation of the NF-κB signalling pathway significantly rescued the expression of inflammatory cytokines and cartilage degradation-related enzymes in the ST-EVs-induced chondrocytes. In conclusion, the ST-EVs promote chondrocytes inflammation and degradation by activating the NF-κB signalling pathway, providing novel insights into the occurrence and development of OA.

Increased Complications in Octogenarians Undergoing Same-Day Discharge following Total Knee Arthroplasty: A Matched Cohort Analysis

Same-day discharge pathways in total knee arthroplasty (TKA) are gaining popularity as a means to increase patient satisfaction and reduce overall costs, but these pathways have not been thoroughly evaluated in potentially at-risk populations, such as in patients ≥80 years old. The purpose of this study was to compare 90-day complications and mortality following same-day discharge after primary TKA in patients ≥80 years old and those <80 years old. Patients who underwent unilateral primary TKA, were discharged on postoperative day 0, and had a minimum 90-day follow-up were identified in a national insurance claims database (PearlDiver Technologies) using Current Procedural Terminology code 27447. These patients were stratified into two cohorts based upon age: (1) nonoctogenarians (<80 years old) and (2) octogenarians (≥80 years old). These cohorts were propensity matched based upon sex, Charlson comorbidity index, and obesity status. Univariate analysis was performed to determine differences in 90-day complications and mortality between the two cohorts. In total, 1,111 patients were included in each cohort. Both cohorts were successfully matched, with no observed differences in matched parameters for demographics or comorbidities. There was no significant difference in 90-day mortality between the two cohorts (p = 0.896). However, octogenarians were at significantly increased risk of postoperative atrial fibrillation (20.8 vs. 10.4%; p < 0.001), nonatrial fibrillation arrhythmias (8.4 vs. 5.6%; p = 0.009), pneumonia (4.5 vs. 2.2%; p = 0.002), stroke (3.1 vs. 1.7%; p = 0.037), heart failure (10.5 vs. 7.5%; p = 0.012), and urinary tract infection (UTI; 14.3 vs. 9.4%; p < 0.001) compared with the nonoctogenarian cohort. Relative to matched controls, octogenarians were at significantly increased risk of numerous 90-day medical complications following same-day primary TKA, including cardiopulmonary complications, stroke, and UTI. Clinicians should be cognizant of these complications and counsel patients appropriately when electing to perform same-day TKA in the octogenarian population.

Comparing Postoperative Readmission Rates Between Veterans Receiving Total Knee Arthroplasty in the Veterans Health Administration Versus Community Care

BACKGROUND

There are growing concerns that Veterans' increased use of Veterans Health Administration (VA)-purchased care in the community may lead to lower quality of care.

OBJECTIVE

We compared rates of hospital readmissions following elective total knee arthroplasties (TKAs) that were either performed in VA or purchased by VA through community care (CC) at both the national and facility levels.

METHODS

Three-year cohort study using VA and CC administrative data from the VA's Corporate Data Warehouse (October 1, 2016-September 30, 2019). We obtained Medicare data to capture readmissions that were paid by Medicare. We used the Centers for Medicare and Medicaid Services (CMS) methods to identify unplanned, 30-day, all-cause readmissions. A secondary outcome, TKA-related readmissions, identified readmissions resulting from complications of the index surgery. We ran mixed-effects logistic regression models to compare the risk-adjusted odds of all-cause and TKA-related readmissions between TKAs performed in VA versus CC, adjusting for patients' sociodemographic and clinical characteristics.

PRINCIPAL FINDINGS

Nationally, the odds of experiencing an all-cause or TKA-related readmission were significantly lower for TKAs performed in VA versus CC (eg, the odds of experiencing an all-cause readmission in VA were 35% of those in CC. At the facility level, most VA facilities performed similarly to their corresponding CC providers, although there were 3 VA facilities that performed worse than their corresponding CC providers.

CONCLUSIONS

Given VA's history in providing high-quality surgical care to Veterans, it is important to closely monitor and track whether the shift to CC for surgical care will impact quality in both settings over time.

Crohn's disease in total knee arthroplasty patients correlates with increased rates of 90-day and overall postoperative complications and readmissions

BACKGROUND

Joint involvement is a common extraintestinal manifestation of Crohn's Disease (CD) that may require total knee arthroplasty (TKA). There is a paucity of evidence regarding the relationship between CD and postoperative outcomes after TKA surgery. This study seeks to evaluate the impact of CD on 90-day and ≥2-year follow-up postoperative outcomes of TKA patients.

METHODS

We retrospectively analyzed the Statewide Planning and Research Cooperative System database (2009-2013) and isolated ICD-9 codes for TKA patients (8154), while excluding those with any revision of knee replacements (0080-0084) and split into 2 groups with or without CD (5550-5559). Patient demographics and postoperative outcomes were compared. Logistic regression analyses with covariates (sex, race, Deyo score, age, and insurance) were utilized to evaluate the association of CD with 90-day and overall postoperative outcomes.

RESULTS

A total of 89,134 TKA patients were identified, 244 of whom had CD. Significant differences in age, race distribution, insurance, and Deyo score (all, p < 0.05) were found. Multivariable analysis demonstrated CD was an independent risk factor for 90-day and overall medical complications, surgical complications, and readmission. Univariate and multivariable analyses report CD had significant increased rates and was a predictor, respectively, of overall blood transfusions (OR 1.5 [95% CI 1.1-2.0] p < 0.01), acute renal failure (OR 1.7 [95% CI 1.1-2.6] p = 0.03), and pulmonary embolism (OR 2.5 [95% CI 1.3-4.6] p = 0.01).

CONCLUSION

Patients with CD undergoing TKA have increased risk both 90-day and overall surgical and medication complications, as well as readmissions compared to patients without CD.

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 ).

Risk factors of postoperative complications following total knee arthroplasty in Korea: A nationwide retrospective cohort study

BACKGROUND

The number of patients undergoing total knee arthroplasty (TKA) is gradually increasing and there is also increase in postoperative complications. The patient's demographic, socio-economic factors, hospital and clinical factors are all factors that can influence postoperative complications. The purpose of this study was to determine the risk factors associated with complications following TKA in a large national cohort.

METHODS

Among patients diagnosed with primary knee arthrosis, a total of 560,954 patients older than 50 years who underwent TKA from January 1, 2005 to December 31, 2018 were included in the study. The risk of postoperative complications (surgical site infection, sepsis, cardiovascular complications, respiratory complications, pulmonary embolism, stroke, acute renal failure, periprosthetic joint infection, and periprosthetic fracture) were assessed with eight independent variables: gender, age, place of residence, household income, hospital bed size, procedure type (unilateral or bilateral, primary or revision TKA), length of stay (LOS), use of transfusion. Multivariable Cox Proportional Hazard model analysis was used. The significant predictors for complications (P < .05) were as follows.

RESULTS

Surgical site infection: male, procedure type (bilateral, revision), LOS (≥35 days), transfusion. Sepsis: male, household income, procedure type (bilateral, revision), LOS (≥35 days), transfusion. Cardiovascular complications: male, age, household income, procedure type (bilateral, revision), LOS (≥35 days), transfusion. Respiratory complications: male, household income, procedure type (bilateral, revision), LOS (≥35 days), transfusion. Pulmonary embolism: male, household income, procedure type (bilateral, revision), LOS (≥35 days), transfusion. Stroke: male, age, procedure type (bilateral, revision), LOS (≥35 days), transfusion. Acute renal failure: male, household income, procedure type (bilateral, revision), LOS (≥35 days), transfusion. Periprosthetic joint infection: male, household income, procedure type (bilateral, revision), LOS (≥35 days), transfusion. Periprosthetic fracture: male, procedure type (bilateral, revision), LOS (≥35 days), transfusion.

CONCLUSION

In summary, male, procedure type (bilateral, revision), LOS (≥35 days), and use of transfusion were shown to be risk factors of postoperative complications following TKA.

Trends in Practice Patterns of Conventional and Computer-assisted Knee Arthroplasty: An Analysis of 570,671 Knee Arthroplasties Between 2010 and 2017

BACKGROUND

Despite advances in computer-assisted knee arthroplasty (CAKA), little is known about the uptake of this technology in recent years. We aimed to explore the utilization trends and practice variation of CAKA from 2010 to 2017 and investigate the predictors of CAKA adoption.

METHODS

Patients undergoing conventional knee arthroplasty and CAKA were identified from the states of New York and Florida's administrative databases using the International Classification of Diseases version 9 and 10 procedure codes. Quarterly proportions of CAKA were calculated over the study period, and logistic regression was used to estimate predictors of CAKA utilization.

RESULTS

Between 2010 and 2017, quarterly proportion of CAKAs increased from 4.89% in 2010Q1 to 9.45% in 2017Q3 in New York and from 4.03% in 2010Q1 to 5.73% in 2017Q3 in Florida. The general CA code was used to code most of the procedures (81%). Being Black (odds ratio [OR]: 0.63, 95% confidence interval [CI], 0.60 to 0.67), Hispanic (OR: 0.45, CI, 0.41 to 0.50), and having Medicaid coverage (OR: 0.46, CI, 0.40 to 0.53) were associated with lower likelihood of receiving CAKA in New York; similar findings were found in Florida.

CONCLUSION

Utilization of CAKA has increased substantially in both New York and Florida from 2010 to 2017; however, with most CAKAs reported using the general code, understanding adoption rates of various modalities was not possible. Black and Hispanic patients and those with Medicaid insurance are least likely to receive this high-precision technology, illustrating the presence of disparities in the adoption of CAKA.

Does Increasing Patient Complexity Have an Effect on Medical Outcomes and Lengths-of-Stay after Total Knee Arthroplasty?

A greater number of medically complex patients with multiple comorbidities are now more readily considered for total knee arthroplasty (TKA). Therefore, the purpose of this study was to determine whether comorbidity burden, measured with the Elixhauser Comorbidity Index (ECI), correlated with 90-day medical complications and longer in-hospital lengths-of-stay (LOS) in TKA patients. The PearlDiver supercomputer was queried for all primary TKA patients in the Medicare Standard Analytic Files from 2005 to 2014 using International Classification of Disease, 9th edition codes. Patients were included based on ECI scores, ranging from 1 to 5. ECI 1 patients served as the control cohort, while ECI 2, 3, 4, and 5 patients were considered study cohorts. Each study cohort was matched based on age and gender to the control cohort, resulting in a total of 715,398 patients included for analysis (ECI 1, n = 144,072; ECI 2, n = 144,072; ECI 3, n = 144,072; ECI 4, n = 144,072; ECI 5, n = 139,110). Logistic regression analyses were performed to compare 90-day medical complications and Welch's t-tests were performed to compare LOS between the cohorts. Patients with higher ECI scores were more likely to develop medical complications and have longer LOS compared with matched patients in the control cohort. Compared with matched ECI 1 patients, patients with ECI scores of 2 (odds ratio [OR]: 1.19, 95% confidence interval [CI]: 1.14-1.24), 3 (OR: 1.27, 95% CI: 1.21-1.32), 4 (OR: 1.32, 95% CI: 1.27-1.38), and 5 (OR: 1.33, 95% CI: 1.27-1.39) were significantly more likely to develop 90-day medical complications. Additionally, the mean LOS of patients in the ECI 2 (2.59 ± 1.49 vs. 2.73 ± 1.52 days), ECI 3 (2.59 ± 1.49 vs. 2.88 ± 1.51 days; p < 0.001), ECI 4 (2.59 ± 1.49 vs. 3.01 ± 1.56 days; p < 0.001), and ECI 5 (2.61 ± 1.49 vs. 3.14 ± 1.61 days; p < 0.001) groups were significantly longer than the mean LOS in the control ECI 1 group. In an increasingly complex patient population, associations between comorbidities and outcomes after TKA procedures can guide providers on how to modify their pre- and postoperative care. These results demonstrate that higher ECI scores are associated with a greater likelihood of 90-day medical complications and longer in-hospital LOS.

Risk Factors for Readmissions After Total Joint Replacement: A Meta-Analysis

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We performed a systematic review and meta-analysis of predictive modeling studies examining the risk of readmission after total hip arthroplasty (THA) and total knee arthroplasty (TKA) in order to synthesize key risk factors and evaluate their pooled effects. Our analysis entailed 15 compliant studies for qualitative review and 17 compliant studies for quantitative meta-analysis.

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A qualitative review of 15 predictive modeling studies highlighted 5 key risk factors for risk of readmission after THA and/or TKA: age, length of stay, readmission reduction policy, use of peripheral nerve block, and type of joint replacement procedure.

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A meta-analysis of 17 studies unveiled 3 significant risk factors: discharge to a skilled nursing facility rather than to home (approximately 61% higher risk), surgery at a low- or medium-procedure-volume hospital (approximately 26% higher risk), and the presence of patient obesity (approximately 34% higher risk). We demonstrated clinically meaningful relationships between these factors and moderator variables of procedure type, source of data used for model-building, and the proportion of male patients in the cohort.

»

We found that many studies did not adhere to gold-standard criteria for reporting and study construction based on the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) and NOS (Newcastle-Ottawa Scale) methodologies.

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We recommend that these risk factors be considered in clinical practice and future work alike as they relate to surgical, discharge, and care decision-making. Future work should also prioritize greater observance of gold-standard reporting criteria for predictive models.

Serious adverse events and 30-day hospital readmission rate following elective total knee arthroplasty: a systematic review and meta-analysis

BACKGROUND

Elective total knee arthroplasty (TKA) is a common surgery which has evolved rapidly. However, there are no recent large systematic reviews of serious adverse event (SAE) rate and 30-day readmission rate (30-dRR) or an indication of whether surgical methods have improved.

METHODS

To obtain a pooled estimate of SAE rate and 30-dRR following TKA, we searched Medline, Web of Science, Cochrane Library, and Google Scholar databases. Data were extracted by two authors following PRISMA guidelines. Eligibility criteria were defined prior to a comprehensive search. Studies were eligible if they were published in 2007 or later, described sequelae of TKA with patient N > 1000, and the SAE or 30-dRR rate could be calculated. SAEs included return to operating room, death or coma, venous thromboembolism (VTE), deep infection or sepsis, myocardial infarction, heart failure or cardiac arrest, stroke or cerebrovascular accident, or pneumonia.

RESULTS

Of 248 references reviewed, 28 are included, involving 10,153,503 patients; this includes 9,483,387 patients with primary TKA (pTKA), and 670,116 patients with revision TKA (rTKA). For pTKA, the SAE rate was 5.7% (95% CI 4.4-7.2%, I2 = 100%), and the 30-dRR was 4.8% (95% CI 4.3-5.4%, I2 = 100%). For rTKA, the SAE rate was 8.5% (95% CI 8.3-8.7%, I2 = 77%), while the 30-dRR was 7.2% (95% CI 6.4-8.0%, I2 = 81%). Odds of 30-dRR following pTKA were about half that of rTKA (OR 0.57, 95% CI 0.53-0.62%, p < 0.001, I2 = 45%). Of patients who received pTKA, the commonest SAEs were VTE (1.22%; 95% CI 0.83-1.70%) and genitourinary complications including renal insufficiency or renal failure (1.22%; 95% CI 0.83-1.67%). There has been significant improvement in SAE rate and 30-dRR since 2010 (χ2 test < 0.001).

CONCLUSIONS

TKA procedures have a relatively low complication rate, and there has been a significant improvement in SAE rate and 30-dRR over the past decade.

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.

Evidence-Based Hospital Procedural Volumes as Predictors of Outcomes After Revision Hip Arthroplasty

BACKGROUND

The aim of this study is to define the evidence-based institutional volume-outcome relationship in revision hip arthroplasty. We hypothesized that high-volume centers would be associated with superior outcomes, and that stratum-specific likelihood ratio (SSLR) analysis would delineate concrete volume thresholds for optimizing outcomes.

METHODS

The Nationwide Readmission Database was queried from 2011 to 2016 for patients undergoing revision hip arthroplasty. SSLR analysis was used to determine hospital volume cutoffs specific for outcomes of interest. Volume categories were confirmed with multivariate regression.

RESULTS

SSLR analysis produced distinct hospital volume cutoffs for all outcomes. Each subsequent volume threshold diminished patients' risk for adverse outcomes. Tertiles were identified for 90-day infection (≤6, 7-51, ≥52 cases per year). Quartiles were found for 90-day readmission (≤5, 6-15, 16-79, ≥80), 90-day prosthesis-related complication (≤5, 6-16, 17-65, ≥66), 90-day dislocation (≤5, 6-19, 20-79, ≥80), and non-home discharge (≤5, 6-15, 16-40, and ≥41). Quintiles were generated for extended length of stay >2 days (≤2, 3-10, 11-20, 21-30, ≥31). Heptiles were produced for medical complications within 90 days (≤2, 3-8, 9-16, 17-51, 52-89, ≥90).

CONCLUSION

This is the first known study to define evidence-based thresholds for the impact of hospital volume on revision joint arthroplasty. This supports the notion that institutional volume functions as a surrogate for protocolized interdisciplinary coordination of care and surgical experience, and that high-volume centers offer enhanced outcomes for complex cases. Additional studies should investigate the potential role for incentivization of such institutions, as they offer optimal outcomes for revision hip arthroplasty.

The Cost-Effectiveness of Platelet-Rich Plasma Injections for Knee Osteoarthritis: A Markov Decision Analysis

BACKGROUND

Use of platelet-rich-plasma (PRP) injections for treating knee osteoarthritis has increased over the past decade. We used cost-effectiveness analysis to evaluate the value of PRP in delaying the need for total knee arthroplasty (TKA).

METHODS

We developed a Markov model to analyze the baseline case: a 55-year-old patient with Kellgren-Lawrence grade-II or III knee osteoarthritis undergoing a series of 3 PRP injections with a 1-year delay to TKA versus a TKA from the outset. Both health-care payer and societal perspectives were included. Transition probabilities were derived from systematic review of 72 studies, quality-of-life (QOL) values from the Tufts University Cost-Effectiveness Analysis Registry, and individual costs from Medicare reimbursement schedules. Primary outcome measures were total costs and quality-adjusted life years (QALYs), organized into incremental cost-effectiveness ratios (ICERs) and evaluated against willingness-to-pay thresholds of $50,000 and $100,000. One and 2-way sensitivity analyses were performed as well as a probabilistic analysis varying PRP-injection cost, TKA delay intervals, and TKA outcomes over 10,000 different simulations.

RESULTS

From a health-care payer perspective, PRP resulted in 14.55 QALYs compared with 14.63 for TKA from the outset, with total health-care costs of $26,619 and $26,235, respectively. TKA from the outset produced a higher number of QALYs at a lower cost, so it dominated. From a societal perspective, PRP cost $49,090 versus $49,424 for TKA from the outset. The ICER for TKA from the outset was $4,175 per QALY, below the $50,000 willingness-to-pay threshold. Assuming the $728 published cost of a PRP injection, no delay time that was <10 years produced a cost-effective course. When the QOL value was increased from the published value of 0.788 to >0.89, PRP therapy was cost-effective with even a 1-year delay to TKA.

CONCLUSIONS

When considering direct and unpaid indirect costs, PRP injections are not cost-effective. The primary factor preventing PRP from being cost-effective is not the price per injection but rather a lack of established clinical efficacy in relieving pain and improving function and in delaying TKA. PRP may have value for higher-risk patients with high perioperative complication rates, higher TKA revision rates, or poorer postoperative outcomes.

LEVEL OF EVIDENCE

Economic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Modifiable Analgesia-/Anesthesia-Related Factors and Risk of Severe Gastrointestinal Complications After Lower Extremity Total Joint Arthroplasty: A Nationwide Analysis

BACKGROUND

Severe gastrointestinal (GI) complications after elective hip and knee arthroplasty (THA/TKA) are rare. Some of them can be life-threatening and/or require emergency abdominal surgery. We studied the epidemiology of severe GI complications after THA/TKA and associations with anesthesia- and/or analgesia-related factors.

METHODS

We included 591,865 THA and 1,139,616 TKA cases (Premier Healthcare claims database; 2006-2016). Main outcomes were GI complications and related emergency surgeries within 30 days after THA/TKA. Anesthesia- and analgesia-related factors were anesthesia type (neuraxial, general), use of peripheral nerve block, patient-controlled analgesia, nonopioid analgesics (acetaminophen, gabapentin/pregabalin, nonsteroidal anti-inflammatory drugs, cyclooxygenase-2 inhibitors, ketamine), and opioids (in oral morphine equivalents, categorized into low, medium, and high use based on the interquartile range). Mixed-effects models measured associations between anesthesia- and analgesia-related factors and outcomes, which were reported using odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Among THA patients, GI complications were observed in 1.03% (n = 6103), with 0.08% (n = 450) requiring emergency surgery; this was 0.79% (n = 8971) and 0.05% (n = 540), respectively, for TKA patients. After adjustment for relevant covariates (including opioid use), almost all anesthesia-/analgesia-related factors were associated with significantly decreased odds of GI complications, specifically use of cyclooxygenase-2 inhibitors (OR 0.72 CI 0.67-0.76/OR 0.82 CI 0.78-0.86), nonsteroidal anti-inflammatory drugs (OR 0.81 CI 0.77-0.85/OR 0.90 CI 0.86-0.94), and peripheral nerve blocks (OR 0.77 CI 0.69-0.87/OR 0.91 CI 0.85-0.97); all for THA and TKA, respectively (all P < .01).

CONCLUSION

Rare, but devastating, acute GI complications (requiring surgery) after THA/TKA may be positively impacted by a variety of modifiable anesthesia-/analgesia-related interventions.

Comparison of readmission and early revision rates as a quality metric in total knee arthroplasty using the Nationwide Readmission Database

Background

After release of the Comprehensive Care for Joint Replacement bundle, there has been increased emphasis on reducing readmission rates for total knee arthroplasty (TKA). The potential for a separate, clinically-relevant metric, TKA revision rates within a year following surgery, has not been fully explored. Based on this, we compared rates and payments for TKA readmission and revision procedures as metrics for improving quality and cost.

Methods

We utilized the 2013 Nationwide Readmission Database (NRD) to examine national readmission and revision rates, the reasons for revision procedures, and associated costs for elective TKA procedures. As data are not linked across years, we examined revision rates for TKA completed in the month of January by capturing revision procedures in the subsequent following 11-month period to approximate a 1-year revision rate. Diagnosis and procedure codes for revision procedures were collected. Average readmission and revision procedure costs were then calculated, and the cost distributed across the entire TKA population.

Results

We identified 20,851 patients having TKA surgery. The mean unadjusted 30- and 90-day TKA readmission rates were 3.4% and 5.8%, respectively. In contrast, the mean unadjusted 3-month and approximate 1-year reoperation rates were 1.0% and 1.6%, respectively. The most common cause for revision was periprosthetic joint infection, which accounting for 62% of all reported revision procedures. The mean payment for 90-day readmission was roughly half ($10,589±$11,084) of the mean inpatient payment for single reoperation procedure at 90 days ($20,222±$17,799). Importantly, nearly half (46%) of all 90-day readmissions were associated with a reoperation event within the first year.

Conclusions

Readmission following TKA is associated with a 1-year reoperation in approximately half of patients. These reoperations represent a significant patient burden and have a higher per episode cost. Early reoperation may represent a more clinically relevant target for quality improvement and cost containment.

The Relationship Between Medicaid Coverage and Outcomes Following Total Knee Arthroplasty: A Systematic Review

BACKGROUND

Access to elective total knee arthroplasty is important in the treatment of end-stage arthritis, and numerous initiatives, including Medicaid expansion, have sought to improve patients' ability to undergo this procedure. However, despite this, the role of Medicaid insurance in patient outcomes remains unclear. The purpose of this study was to perform a systematic review of the literature to explore the relationship between preoperative Medicaid insurance status and outcomes following primary total knee arthroplasty.

METHODS

A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify studies examining outcomes in patients who had Medicaid and were undergoing total knee arthroplasty. Studies including complex revision operations or less common indications for total knee arthroplasty were excluded. Data on insurance status, postoperative complications, length of stay, readmissions, and subsequent revision surgical procedures were collected for each article.

RESULTS

A total of 13 studies showing 6.18 million patients undergoing total knee arthroplasty were included in the qualitative synthesis. Seven analyses described an important association between Medicaid coverage and short-term readmissions, and 2 analyses showed a relationship between Medicaid and prolonged length of stay. However, the included studies did not describe a significant association between Medicaid and postoperative mortality or revision rates.

CONCLUSIONS

Patients with Medicaid undergoing total knee arthroplasty may be more likely to experience an increased length of stay and to be readmitted postoperatively. The unique factors associated with these patients may help to inform customized perioperative surveillance and optimization to improve outcomes in this group.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Defining the Volume-Outcome Relationship in Reverse Shoulder Arthroplasty: A Nationwide Analysis

BACKGROUND

As the utilization of reverse total shoulder arthroplasty (RSA) grows, it is increasingly important to examine the relationship between hospital volume and RSA outcomes. We hypothesized that hospitals that perform a higher volume of RSAs would have improved outcomes. We also performed stratum-specific likelihood ratio (SSLR) analysis with the aim of delineating concrete definitions of hospital volume for RSA.

METHODS

The Nationwide Readmissions Database was queried for patients who had undergone elective RSA from 2011 to 2015. Annual hospital volume and 90-day outcome data were collected, including readmission, revision, complications, hospital length of stay (LOS), supramedian cost, and discharge disposition. SSLR analysis was performed to determine hospital volume cutoffs associated with increased risks for adverse events. Cutoffs generated through SSLR analysis were confirmed via binomial logistic regression.

RESULTS

The proportion of patients receiving care at high-volume centers increased from 2011 to 2015. SSLR analysis produced hospital volume cutoffs for each outcome, with higher-volume centers showing improved outcomes. The volume cutoffs associated with the best rates of 90-day outcomes ranged from 54 to 70 RSAs/year, whereas cost and resource utilization cutoffs were higher, with the best outcomes in hospitals performing >100 RSAs/year. SSLR analysis of 90-day readmission produced 3 hospital volume categories (1 to 16, 17 to 69, and ≥70 RSAs/year), each significantly different from each other. These were similar to the strata for 90-day revision (1 to 16, 17 to 53, and ≥54 RSAs/year) and 90-day complications (1 to 9, 10 to 68, and ≥69 RSAs/year). SSLR analysis produced 6 hospital volume categories for cost of care over the median value (1 to 5, 6 to 25, 26 to 47, 48 to 71, 72 to 105, and ≥106 RSAs/year), 5 categories for an extended LOS (1 to 10, 11 to 25, 26 to 59, 60 to 105, and ≥106 RSAs/year), and 4 categories for non-home discharge (1 to 31, 32 to 71, 72 to 105, and ≥106 RSAs/year).

CONCLUSIONS

We have defined hospital surgical volumes that maximize outcomes after RSA, likely related to surgical experience, ancillary staff familiarity, and protocolized pathways. This information may be used in future policy decisions to consolidate complex procedures, such as RSA, at high-volume destinations, or to encourage lower-volume institutions to strategize an approach to function as a higher-volume center.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Computerized navigation for total hip arthroplasty is associated with lower complications and ninety-day readmissions: a nationwide linked analysis

INTRODUCTION

The objective was to evaluate if the use of CA-THA was associated with lower complications in the first 90 days following THA compared with conventional THA.

METHODS

The Nationwide Readmission Database (NRD) was queried to identify patients who underwent THA between 2012 and 2014. The primary outcome was arthroplasty-related complications within the first 90 days following THA. Multivariate models predicting the risk of complications, readmission, and revision-related readmission within 90 days of discharge were created.

RESULTS

A total of 309,252 patients with a minimum 90-day follow-up following elective primary THA were identified. After controlling for age, sex, comorbidities, indication, income, and type of insurance, the use of CA during THA resulted in a 12% reduced odds of 90-day complications (OR 0.88, 95% CI 0.77-0.99, p = 0.04).

DISCUSSION

The use of CA-THA resulted in lower 90-day complication rates and readmission rates compared with traditional THA after controlling for confounding variables. There was no significant difference in the rates of revision surgery between the groups within the first 90 days.

Highlighting the Roles of Anemia and Aspirin in Predicting Ninety-Day Readmission Following Aseptic Revision Total Joint Arthroplasty

BACKGROUND

Revision total joint arthroplasties (TJAs) are associated with an increased rate of complications. To date, it is unclear what drives readmission after aseptic revision arthroplasty and what measures can be taken to possibly avoid them. The purpose of this study is to (1) determine the reasons for readmission after aseptic revision TJA and (2) identify patient-specific or postoperative risk factors through a multivariate analysis.

METHODS

A retrospective study examined 1503 cases of aseptic revision TJA between 2009 and 2016 at an urban tertiary care hospital. Eighty-seven cases (5.8%) of readmission within 90 days of index surgery were identified. Bivariate and multivariate analyses were performed to assess independent risk factors for readmission.

RESULTS

The reasons for readmission were infection (38%), wound complications (22%), and dislocation/instability of the prosthetic joint (13%). Only preoperative anemia was associated with an increased odds ratio (OR) of readmission (OR 1.82, 95% confidence interval [CI] 1.126-2.970, P = .015), whereas postoperative venous thromboembolism prophylaxis with aspirin (OR 0.58, 90% CI 0.340-0.974, P = .039) and discharge to an inpatient rehab facility (OR 0.22, 95% CI 0.051-0.950, P = .042) were associated with significantly lower odds of readmission.

CONCLUSION

Based on this single institutional study, addressing preoperative anemia and considering the implementation of aspirin for venous thromboembolism prophylaxis may be 2 targets to potentially reduce readmission after aseptic revision TJA.

Temporal Trends and Predictors of Thirty-Day Readmissions and Emergency Department Visits Following Total Knee Arthroplasty in Ontario Between 2003 and 2016

BACKGROUND

Total knee arthroplasty (TKA) is the second most common surgery performed in Canada. Understanding and improving quality metrics associated with such high-volume procedures is of utmost importance to maximize value within the healthcare system, which is a balance between cost and quality. Although rates and predictors of hospital readmission and emergency department (ED) visits following TKA have previously been described in privatized healthcare settings, few studies have evaluated trends in length of stay (LOS), hospital readmissions, and ED visits following TKA in a universal single-payer system.

METHODS

Using data from a provincially held and validated registry, the Institute for Clinical and Evaluative Sciences, we undertook a review of all 205,152 TKAs performed in the province of Ontario, Canada, between 2003 and 2016. We determined temporal trends in utilization, LOS, readmissions, and ED visits and evaluated patient and provider predictors of hospital readmissions and ED visits using multivariate logistic regression modeling. We also grouped and described the most common reasons for readmission and ED visits based on the available International Classification of Diseases, Ninth Revision and Tenth Revision coding information.

RESULTS

LOS decreased significantly over the study period (P < .0001), from a median of 5 days (10th percentile 3 days, 90th percentile 8 days) in 2003 to a median of 3 days (10th percentile 2 days, 90th percentile 4 days) in 2016. All-cause 30-day readmissions did not change significantly over the study period, but the rate of ED visits increased significantly over time. Predictors of 30-day readmission following TKA included older age, male gender, lower income quartile, not having a postoperative visit with a primary care physician (PCP), increased comorbidities, longer LOS, urgent or revision surgery, admission to a teaching hospital, and discharge to an inpatient rehabilitation facility. Variables that predicted increased odds of an ED visit included older age, male gender, lower income quartile, not having a postop visit with a PCP, increasing comorbidities, year of surgery, longer LOS, and revision surgery. Admission to a teaching hospital and discharge to an inpatient rehabilitation facility showed a trend toward increased odds of an ED visit.

CONCLUSIONS

We identified a significant increase in ED visits following TKA in Ontario between 2003 and 2016, with no corresponding increase in hospital readmissions despite a significant temporal trend toward shorter LOS. Predictors of ED visits and readmissions were similar, including male gender, lower income, higher comorbidities, and lacking a PCP visit postoperatively. Increased rates of ED visits following TKA in Ontario represent a quality problem, as they are associated with increased cost to the public healthcare system without any substantial benefit. Interventions aimed at redirecting patients from the ED for minor postoperative concerns should be investigated, as this is likely to improve care by reducing costs, improving efficiency, and enhancing patient experience.

Patient-related risk factors for unplanned 30-day readmission following total knee arthroplasty: a narrative literature review

Osteoarthritis is a debilitating condition as well as a growing global health problem, and total knee arthroplasty (TKA) is an effective treatment for advanced disease. Unplanned 30-day hospital readmission is an indicator of complications, which is a significant financial burden on healthcare systems. We reviewed the literature to better understand the patient-related factors associated with unplanned 30-day readmission following TKA. MEDLINE and EMBASE were searched for studies reporting on patient-related risk factors for unplanned 30-day readmission following primary or revision TKA for any indication. The impact of specific medical comorbidities on increasing the risk of 30-day readmission following TKA is quite well established. The following comorbidities are strongly associated with readmission: bleeding disorder, diabetes, chronic kidney disease and dialysis, chronic immunosuppressant use and history of cancer. Other significant comorbidities include: dementia; depression; haematological (coagulopathy and anaemia), cardiovascular (atrial fibrillation, cardiovascular disease, coronary artery disease and congestive heart failure), respiratory (chronic obstructive pulmonary disease) and liver diseases; and cerebrovascular accident/transient ischaemic attack (but only in revision TKA patients). The influence of variation in sex, age and body mass index each demonstrate a more complex pattern. A systematic review and meta-analysis is required to quantify the impact of the various patient-related factors on 30-day readmission following TKA. Clinicians can use this information in preoperative decision-making.

Modern instant messaging platform for postoperative follow-up of patients after total joint arthroplasty may reduce re-admission rate

BACKGROUND

Follow-up after artificial joint replacement greatly helps achieve surgical outcomes. Mobile internet technology and mobile terminal equipment may increase the effectiveness of artificial joint replacement. However, only a few studies have evaluated the effectiveness of this technology. We aimed to analyze the reasons and outcomes of patients who used the instant messaging platform after undergoing artificial joint replacement.

METHODS

Among the 548 cases of arthroplasty (250 hips, 298 knees) performed between December 2015 and June 2018 in the Department of Joint Surgery of our institution; 358 (164 hip joints, 194 knee joints) participated in instant messaging platform consultation, whereas the remaining 190 (86 hip joints, 104 knee joints) participated in traditional telephone consultation, as a control group. Follow-up time was from December 2015 to August 2018 (follow-up period was 2-32 months). Data on age, sex, type of surgery, date of surgery, date of discharge, and length of hospital stay were collected from electronic medical records.

RESULTS

We analyzed the consultation contents of 358 patients who participated in instant messaging platform consultation. Counseling was mainly related to pain (13.6%), appointment review (12.4%), activity problems (10.5%), and incision problems (8.9%). Most problems were resolved through online guidance, with 8.4% of patients requiring only outpatient treatment and 2.5% of patients requiring rehospitalization. A total of 190 patients were followed up through traditional telephone consultation; 6.8% of patients required outpatient department treatment and 7.4% were eventually re-admitted.

CONCLUSION

The instant messaging platform consultation service effectively informs patients of potential postoperative problems and helps resolve them. It allows early detection and management of postoperative adverse events, including problems related to medication, wound, and activity, thereby effectively reducing readmission rate.

Intra-articular platelet-rich plasma injection for knee osteoarthritis: a summary of meta-analyses

OBJECTIVE

The purpose of this study was (1) to perform a summary of meta-analyses comparing platelet-rich plasma (PRP) injection with hyaluronic acid (HA) and placebo injection for KOA patients, (2) to determine which meta-analysis provides the best available evidence to making proposals for the use of PRP in the treatment of KOA patients, and (3) to highlight gaps in the literature that require future investigation.

MATERIAL AND METHODS

PubMed, EMBASE, and Cochrane databases search were performed for meta-analyses which compared PRP injection with HA or placebo. Clinical outcomes and adverse events were extracted from these meta-analyses. Meta-analysis quality was assessed using the Quality of Reporting of Meta-analyses (QUOROM) systems and the Oxman-Guyatt quality appraisal tool. The Jadad decision algorithm was also used to determine which meta-analysis provided the best available evidence.

RESULTS

Four meta-analyses were included in our study, and all of these articles were Level I evidence. The QUOROM score of each included meta-analysis range from 14 to 17 points (mean score 15, maximum score 18), and the Oxman-Guyatt score range from 4 to 6 points (mean score 5, maximum score 7). Three meta-analyses indicated PRP showed more benefit in pain relief and functional improvement than the control group, and the other one suggested no difference between these groups. All included meta-analyses found no statistical difference in adverse events between these groups. In addition, a meta-analysis conducted by Shen et al. got the highest methodological quality score and suggested that PRP provided better pain relief and function improvement in the treatment of KOA.

CONCLUSIONS

For short-term follow-up (≤1 year), intra-articular PRP injection is more effective in terms of pain relief and function improvement in the treatment of KOA patients than HA and placebo, and there is no difference in the risk of an adverse event between PRP and HA or placebo.

LEVEL OF EVIDENCE

Level I evidence, a summary of meta-analyses TRIAL REGISTRATION: PROSPERO ID CRD42018116168.

Reductions in Race and Ethnic Disparities in Hospital Readmissions Following Total Joint Arthroplasty from 2005 to 2015

BACKGROUND

Racial and ethnic disparities in hospital readmissions following total joint arthroplasty present opportunities for reducing cost and improving health equity. Despite efforts to reduce readmissions following total joint arthroplasty in the general population, no studies have documented the impact of these efforts on racial and ethnic disparities in total joint arthroplasty readmissions. The purpose of this study was to determine whether comprehensive efforts to reduce hospital readmissions following total joint arthroplasty have impacted racial and ethnic disparities in readmission rates during the period from 2005 to 2015.

METHODS

We conducted a retrospective analysis comparing patients readmitted and not readmitted to the hospital within 30 days of a total joint arthroplasty by estimating logistic regression models for clustered data using generalized estimating equations (GEEs) in R. Connecticut hospital discharge data for patients admitted for International Classification of Diseases, Ninth Revision (ICD-9) procedure codes 81.51 and 81.54 (Current Procedural Terminology [CPT] codes 27130 and 27447) during the 2005 to 2015 U.S. Centers for Medicare & Medicaid Services (CMS) fiscal years were analyzed. Models included quadratic terms to capture nonlinear time trends in readmissions, as well as terms for the statistical interaction between race or ethnicity and both the linear and quadratic time trends in predicting the odds of readmission.

RESULTS

There were 102,510 total admissions to Connecticut hospitals for total joint arthroplasty from 2005 to 2015. The 30-day (all-cause) readmission rate declined from 5.1% in 2005 to 3.6% in 2015, with a steeper downward trend observed from 2009 to 2015. The results from logistic models indicated that black patients (odds ratio [OR], 1.68; p < 0.0001) and Hispanic patients (OR, 1.48; p < 0.0001) were significantly more likely to be readmitted within 30 days of discharge following a total joint arthroplasty than white patients over the study period. The significant interaction of black race and the quadratic time trend in models capturing nonlinear trends in readmission over time indicated that the readmission rates for black patients increased compared with those for white patients from 2005 through 2008 and decreased relative to those for white patients from 2009 to 2015 (OR, 0.24; p = 0.030).

CONCLUSIONS

Data from Connecticut hospitals show that 30-day readmissions following a total joint arthroplasty declined by 1.5 percentage points from 2005 to 2015, and that this decline was much more pronounced among black patients, resulting in the narrowing of racial disparities in readmission following a surgical procedure.

CLINICAL RELEVANCE

Racial and ethnic minorities have historically been at increased risk for complications and readmission following hospital-based surgical care. This analysis of readmission following total joint arthroplasty reveals that such disparities are remediable and should foster further research on the primary drivers of and remedies for readmission disparities.

Medicaid insurance status predicts postoperative mortality after total knee arthroplasty in state inpatient databases

Aim: Medicaid versus private primary insurance status may predict in-hospital mortality and morbidity after total knee arthroplasty (TKA). Materials & methods: Regression models were used to test our hypothesis in patients in the State Inpatient Database (SID) from five states who underwent primary TKA from January 2007 to December 2014. Results: Medicaid patients had greater odds of in-hospital mortality (odds ratio [OR]: 1.73; 95% CI: 1.01-2.95), greater odds of any postoperative complications (OR: 1.25; 95% CI: 1.18-1.33), experience longer lengths of stay (OR: 1.09; 95% CI: 1.08-1.10) and higher total charges (OR: 1.03; 95% CI: 1.02-1.04). Conclusion: Medicaid insurance status is associated with higher in-hospital mortality and morbidity in patients after TKA compared with private insurance.

Patterns and Costs of 90-Day Readmission for Surgical and Medical Complications Following Total Hip and Knee Arthroplasty

BACKGROUND

Unplanned readmissions following elective total hip (THA) and knee (TKA) arthroplasty as a result of surgical complications likely have different quality improvement targets and cost implications than those for nonsurgical readmissions. We compared payments, timing, and location of unplanned readmissions with Center for Medicare and Medicaid Services (CMS)-defined surgical complications to readmissions without such complications.

METHODS

We performed a retrospective analysis on unplanned readmissions within 90 days of discharge following elective primary THA/TKA among Medicare patients discharged between April 2013 and March 2016. We categorized unplanned readmissions into groups with and without CMS-defined complications. We compared the location, timing, and payments for unplanned readmissions between both readmission categories.

RESULTS

Among THA (N = 23,231) and TKA (N = 43,655) patients with unplanned 90-day readmissions, 27.1% (n = 6307) and 16.4% (n = 7173) had CMS-defined surgical complications, respectively. These readmissions with surgical complications were most commonly at the hospital of index procedure (THA: 84%; TKA: 80%) and within 30 days postdischarge (THA: 73%; TKA: 77%). In comparison, it was significantly less likely for patients without CMS-defined surgical complications to be rehospitalized at the index hospital (THA: 63%; TKA: 63%; P < .001) or within 30 days of discharge (THA: 58%; TKA: 59%; P < .001). Generally, payments associated with 90-day readmissions were higher for THA and TKA patients with CMS-defined complications than without (P < .001 for all).

CONCLUSION

Readmissions associated with surgical complications following THA and TKA are more likely to occur at the hospital of index surgery, within 30 days of discharge, and cost more than readmissions without CMS-defined surgical complications, yet they account for only 1 in 5 readmissions.

Operative Times Have Remained Stable for Total Hip Arthroplasty for >15 Years: Systematic Review of 630,675 Procedures

Understanding trends in operative times has become increasingly important in light of total hip arthroplasty (THA) being added to the Centers for Medicare & Medicaid Services (CMS) 2019 Potentially Misvalued Codes List. The purpose of this review was to explore the mean THA operative times reported in the literature in order (1) to determine if they have increased, decreased, or remained the same for patients reported on between 2000 and 2019 and (2) to determine what factors might have contributed to the difference (or lack thereof) in THA operative time over a contemporary study period.

METHODS

The PubMed and EBSCOhost databases were queried to identify all articles, published between 2000 and 2019, that reported on THA operative times. The keywords used were "operative," "time," and "total hip arthroplasty." An article was included if the full text was available, it was written in English, and it reported operative times of THAs. An article was excluded if it did not discuss operative time; it reported only comparative, rather than absolute, operative times; or the cohort consisted of total knee arthroplasties (TKAs) and THAs, exclusively of revision THAs, or exclusively of robotic THAs. Data on manual or primary THAs were extracted from studies including robotic or revision THAs. Thirty-five articles reporting on 630,675 hips that underwent THA between 1996 and 2016 met our criteria.

RESULTS

The overall weighted average operative time was 93.20 minutes (range, 55.65 to 149.00 minutes). When the study cohorts were stratified according to average operative time, the highest number fell into the 90 to 99-minute range. Operative time was stable throughout the years reported. Factors that led to increased operative times included increased body mass index (BMI), less surgical experience, and the presence of a trainee.

CONCLUSIONS

The average operative time across the included articles was approximately 95 minutes and has been relatively stable over the past 2 decades. On the basis of our findings, we cannot support CMS lowering the procedural valuation of THA given the stability of its operative times and the relationship between operative time and cost.

Patient-related risk factors for unplanned 30-day readmission following total knee arthroplasty: a protocol for a systematic review and meta-analysis

BACKGROUND

Osteoarthritis is a debilitating condition as well as a growing global health problem, and total knee arthroplasty is an effective treatment for advanced stages of disease. Unplanned 30-day hospital readmission is an indicator of complications, which is a significant financial burden on healthcare systems. The objective is to perform a systematic review of patient-related factors associated with unplanned 30-day readmission following total knee arthroplasty. This information will inform future strategies to improve health outcomes after knee arthroplasty surgery.

METHODS

MEDLINE and EMBASE will be systematically searched using a comprehensive search strategy. Studies of higher quality than case series will be included, in order to optimise the quality of the findings of this review. We will include studies reporting on patient-related risk factors for unplanned 30-day readmission following primary or revision total knee arthroplasty for any indication. Case series will be excluded, as will studies reporting exclusively on intraoperative, clinician, hospital, and health system risk factors. The reference lists of selected papers will then be screened for any additional literature. Two reviewers will independently apply stringent eligibility criteria to titles, abstracts, and full texts of studies identified in the literature search. They will then extract data from the final list of selected papers according to an agreed-upon taxonomy and vocabulary of the data to be extracted. Assessment of risk of bias and quality of evidence will then take place. Finally, the effect size of each identified risk factor will be determined; meta-analysis will be performed where adequate data is available.

DISCUSSION

The findings of this review and subsequent meta-analysis will aid clinicians as they seek to understand the risk factors for 30-day readmission following total knee arthroplasty. Clinicians and patients will be able to use this information to align expectations of the postoperative course, which will enhance the recovery process, and aid in the development of strategies to mitigate identified risks. Another purpose of this review is to assist policy-makers in developing quality indicators for care and provide insights into the drivers of health costs.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019118154.

Who Cares for Total Hip Arthroplasty Complications? Rates of Readmission to a Hospital Different From the Location of the Index Procedure

INTRODUCTION

While the number of total hip arthroplasties (THAs) performed increases, so is the number of postoperative readmissions, resulting in costly episodes of care that may disproportionately affect certain hospitals. This study examines the rates of readmission of patients to the same hospital at which they underwent index THA, compared with readmission to a different hospital.

METHODS

Data for all hospital discharges from 1995 to 2010 were obtained from the California Office of Statewide Health Planning and Development database. Patient outcomes, readmission data, demographic information, hospital teaching status, and location were analyzed. Regression modeling was used to evaluate the effect of hospital teaching status, location, and individual complications on the risk of readmission to the same hospital as opposed to a different hospital following the index procedure.

RESULTS

The overall postoperative readmission rate for specific defined complications or all-cause 30-day readmissions was 3.92%, with 75.17% readmitted to the same hospital. Following index THA at a nonacademic or academic hospital, 95.9% and 84.6% of patients were readmitted to the same type of hospital, respectively. Patients who had their index procedure at an academic hospital had lower odds for readmission to the same hospital (odds ratio, 0.734; P < 0.0001) compared with nonacademic centers. Hospitals in midsize towns had higher odds of readmission to the same hospital (odds ratio, 1.735; P = 0.0012) compared with those in large metropolitan areas.

DISCUSSION

Although more than 75% of patients with unplanned readmissions went to the same hospital as their index THA, academic and larger metropolitan hospitals had higher odds of postoperative readmissions to a different hospital.

The Effect of Race on Early Perioperative Outcomes After Shoulder Arthroplasty: A Propensity Score Matched Analysis

There is a paucity of data on how racial disparities may affect early outcomes following shoulder arthroplasty. The purpose of this study was to evaluate differences in 30-day complications and readmission rates after shoulder arthroplasty based on race. White and black patients who underwent hemiarthroplasty, anatomic or reverse total shoulder arthroplasty (Current Procedural Terminology codes 23470 and 23472) between 2006 and 2015 were identified in the American College of Surgeons National Surgical Quality Improvement Program database. Black patients were propensity score matched 1:4 based on preoperative demographics and comorbidities to white patients. Multivariable analysis was performed to assess postoperative complications based on race. Of the 12,663 patients with shoulder arthroplasty identified, 10,717 (84.6%) were white and 559 (4.4%) were black. Overall, 557 black patients were matched to 2228 white patients, for a total cohort of 2785 patients (mean age, 63.9±11.7 years; female, 61.0%). Surgical indications were similar between black and white patients. The 2 races had similar rates of overall complications, major complications, minor complications, readmissions, and discharge to facility. Mortality was significantly higher among black patients compared with white patients (0.6% vs 0.05%; P=.033). Black patients also experienced longer operative time (mean, 126.4 vs 112.5 minutes; P<.001) and length of stay (mean, 2.4 vs 2.1 days; P<.001). There was a significant disparity with underutilization of shoulder arthroplasty for black patients in the American College of Surgeons National Surgical Quality Improvement Program database. Black and white patients undergoing shoulder arthroplasty experienced similar rates of 30-day complications, readmissions, and discharge to facility. However, black patients experienced greater operative time, total length of stay, and mortality compared with white patients. [Orthopedics. 2019; 42(2):95-102.].

G, Shah A, Godoy-Santos AL, Naranje S. RISK FACTORS FOR EARLY HOSPITAL READMISSION FOLLOWING TOTAL KNEE ARTHROPLASTY

Objective

To identify independent risk factors, complications and early hospital readmission following total knee arthroplasty.

Methods

Using the ACS-NSQIP database, we identified patients who underwent primary TKA from 2012-2015. The primary outcome was early hospital readmission. Patient demographics, preoperative comorbidities, laboratory data, operative characteristics, and postoperative complications were compared between readmitted and non-readmitted patients. Logistic regression identified independent risk factors for 30-day readmission.

Results

137,209 patients underwent TKA; 3.4% were readmitted within 30 days. Advanced age, male sex, black ethnicity, morbid obesity, presence of preoperative comorbidities, high ASA classification, and increased operative time were independently related risk factors. Asian and no reported race were negative risk factors. Postoperative complications: acute myocardial infarction, acute renal failure, stroke, pneumonia, pulmonary embolism, and deep vein thrombosis show positive associations.

Conclusions

Advanced age, male sex, black ethnicity, morbid obesity, presence of comorbidities, high ASA classification and long operative time are independent risk factors for postoperative complications and early hospital readmission following total knee arthroplasty. Level of Evidence III, Case control study.