Advantages of robotic arm-assisted total hip arthroplasty: a 90-day episode-of-care clinical utility and cost analysis.

Aim: Determine the clinical utility and economic differences over a 90-day period between robotic arm-assisted total hip arthroplasty (RATHA) and manual total hip arthroplasty (MTHA). Methods: Leveraging a nationwide commercial payer database, pre-covid THA procedures were identified. Following a 1:5 propensity score match, 1732 RATHA and 8660 MTHA patients were analyzed. Index costs, index lengths of-stay, and 90-day episode-of-care utilization and costs were evaluated. Results: Episode of care costs for RATHA was found to be $1573 lower compared with MTHA (p < 0.0001). Post-index hospital utilization was significantly less likely to occur for RATHA compared with MTHA. Total index costs were also significantly lower for RATHA versus MTHA (p < 0.0001). Conclusion: Index and post-index EOC hospital utilization and costs were lower for RATHA compared with MTHA.

Positive COVID-19 Diagnosis Following Primary Elective Total Joint Arthroplasty: Increased Complication and Mortality Rates.

BACKGROUND: This study analyzed complication rates following primary elective total joint arthroplasty (TJA) in patients who subsequently contracted COVID-19. METHODS: A large national database was queried for adult patients who underwent primary elective TJA in 2020. Patients who contracted COVID-19 after total knee arthroplasty (TKA) or total hip arthroplasty (THA) underwent 1:6 matching (age [±6 years], sex, month of surgery, COVID-19-related comorbidities) to patients who did not. Differences between groups were assessed using univariate and multivariate analyses. Overall, 712 COVID-19 patients were matched to 4,272 controls (average time to diagnosis: 128-117 days [range, 0-351]). RESULTS: Of patients diagnosed <90 days postoperatively, 32.5%-33.6% required COVID-19-driven readmission. Discharge to a skilled nursing facility (adjusted odds ratio [aOR] 1.72, P = .003) or acute rehabilitation unit (aOR 4.93, P < .001) and Black race (aOR 2.28, P < .001) were associated with readmission after TKA. Similar results were associated with THA. COVID-19 patients were at increased risk of pulmonary embolism (aOR 4.09, P = .001) after TKA and also periprosthetic joint infection (aOR 4.65, P < .001) and sepsis (aOR 11.11, P < .001) after THA. The mortality rate was 3.51% in COVID-19 patients and 7.94% in readmitted COVID-19 patients compared to 0.09% in controls, representing a 38.7 OR and 91.8 OR of death, respectively. Similar results were observed for TKA and THA separately. CONCLUSION: Patients who contracted COVID-19 following TJA were at greater risk of numerous complications, including death. These patients represent a high-risk cohort who may require more aggressive medical interventions. Given the potential limitations presently, prospectively collected data may be warranted to validate these findings.

Higher Complication Rate in COVID-19 Recovered Patients Undergoing Primary Total Joint Arthroplasty.

BACKGROUND: There is limited data reviewing complication risks associated with total joint arthroplasty (TJA) after recovering from COVID-19. This study evaluated complications within 90 days of TJA in patients who had a COVID-19 diagnosis at varying intervals prior to surgery versus a non-COVID-19 cohort. METHODS: A large national database was used to identify patients diagnosed with COVID-19 in the six months prior to total hip arthroplasty (THA) or total knee arthroplasty. The incidence of complications within 90 days of surgery was recorded and compared to a COVID-19 negative control group matched 1:3 for age range in 5-year intervals, Charlson Comorbidity Index, and sex. There were 7,780 patients included in the study; 5,840 (75.1%) never diagnosed with COVID-19, 1,390 (17.9%) who had a COVID-19 diagnosis 0 to 3 months prior to surgery, and 550 (7.1%) who had a COVID-19 diagnosis 3 to 6 months prior to surgery. RESULTS: When compared to their COVID negative controls, patients who had a COVID-19 diagnosis 0 to 3 months prior to surgery had significantly higher rates of readmission (14.0 versus 11.1%, P = .001), pneumonia (2.2 versus 0.7%, P < .001), deep vein thrombosis (DVT) (3.3 versus 1.9%, P = .001), kidney failure (2.4 versus 1.4%, P = .006), and acute respiratory distress syndrome (1.4 versus 0.7%, P = .01). Patients who had a COVID-19 diagnosis 3 to 6 months prior to surgery had significantly higher rates of pneumonia (2.0 versus 0.7%, P = .002) and DVT (3.6 versus 1.9%, P = .005) when compared to their COVID negative controls. CONCLUSION: Patients diagnosed with COVID-19 within three months prior to TJA have an increased risk of 90-day postoperative complications. Risk for pneumonia and DVT remains elevated even when surgery was performed as far as 3 to 6 months after COVID-19 diagnosis.

Patients With Previous COVID-19 Infection Can Safely Undergo Primary Total Joint Arthroplasty.

BACKGROUND: The COVID-19 virus is believed to increase the risk of diffusing intravascular coagulation. Total joint arthroplasty (TJA) is one of the most common elective surgeries and is also associated with a temporarily increased risk of venous thromboembolism (VTE). However, the influence of a history of COVID-19 infection on perioperative outcomes following TJA remains unknown. Therefore, this study sought to determine what effect a history of COVID-19 infection had on outcomes following primary TJA. METHODS: A retrospective case-control study using the national database was performed to identify all patients who had a history of COVID-19 and had undergone TJA, between 2019 and 2020. Patients who had a history of both were 1:1 matched to those who did not have a history of COVID-19, and 90-day outcomes were compared. A total of 661 TKA and 635 THA patients who had a history of COVID-19 were 1:1 matched to controls. There were no differences in demographics and comorbidities between the propensity-matched pairs in both TKAs and THAs studied. Previous COVID-19 diagnosis was noted in 28.3% of patients 5 days within TJA and in 78.6%, 90 days before TJA. RESULTS: Patients who had a previous diagnosis of COVID-19 had a higher risk of pneumonia during the postoperative period for both THA and TKA (6.9% versus 3.5%, P < .001 and 2.27% versus 1.21%, P = .04, respectively). Mean lengths of stay were also greater for those with a previous COVID-19 infection in both cohorts (TKA: 3.12 versus 2.57, P = .027, THA: 4.52 versus 3.62, P < .001). Other postoperative outcomes were similar between the 2 groups. CONCLUSION: COVID-19 infection history does not appear to increase the risk of VTE following primary TJA, but appears to increase the risk of pneumonia in addition to lengths of stay postoperatively. Individual risk factors should be discussed with patients, to set reasonable expectations regarding perioperative outcomes.

Unexpected Repercussions of the COVID-19 Pandemic on Total Hip Arthroplasty with Cemented Hip Prosthesis versus Cementless Implants.

(1) Background: Total hip arthroplasty (THA) is one of the most common procedures used for adult hip reconstruction, employing mainly two types of prostheses: cemented (CHP) and cementless (CLHP). This study aims to analyze the impact of the COVID-19 pandemic on THA with CHP and CLHP, in terms of the benefit/cost ratio. (2) Methods: This article represents a retrospective analysis of the differences concerning the benefit/cost ratio between THA with the two types of prostheses in 2950 patients admitted for THA in the two orthopedic clinics of our hospital between 1 January 2015-1 March 2020 in comparison with 1005 THA subjects seen between 1 April 2020-31 December 2022. (3) Results: In the first period, THA with CHP was performed in 45.83% of cases, while CLHP was used in 54.16% of patients. During the COVID-19 period, CHP was inserted in 52% of THA patients, while the other 48% had CLHP inserted, with a hospitalization duration reduced by over 50% for both types of implants (p ˂ 0.001). (4) Conclusions: CHP offered good outcomes, with quicker mobilization, and shorter hospitalization duration, compared to CLHP, but optimization of the patients' management can be achieved mainly by reducing the length of hospitalization through an appropriate preoperative patient evaluation through a multidisciplinary approach, an aspect that was proven during the COVID-19 pandemic.

An Increase in Same-day Discharge After Total Joint Arthroplasty During the COVID-19 Pandemic Does Not Influence Patient Outcomes: A Retrospective Cohort Analysis.

Background: The coronavirus disease 2019 (COVID-19) pandemic caused major transitions in total joint arthroplasty (TJA), notably with the increased utilization of same-day discharge (SDD) pathways. This study assessed the effect of accelerated discharge pathways following the resumption of elective cases during the COVID-19 pandemic on SDD rates, adverse events, and characteristics associated with successful SDD following total hip and total knee arthroplasty. Methods: This retrospective study split patients into cohorts: TJA prior to COVID-19 (pre-COVID, July 2019-December 2019) and TJA following the resumption of elective surgeries (post-COVID, July 2020-December 2020). Patient characteristics such as age, sex, body mass index, American Society of Anesthesiologists score, and pertinent comorbidities were analyzed, and length of stay, 30-day emergency department (ED) visit rates, readmissions, and reoperations were compared. Results: A total of 1333 patients met inclusion criteria that were divided into pre-COVID (692) and post-COVID (641) cohorts. The pre-COVID group had a median age of 69 years (interquartile range 63-76), and the post-COVID group had a median age of 68 years (interquartile range 61-75) (P = .024). SDD increased from 0.1% to 28.9% (P < .001), and length of stay decreased from 1.3 days to 0.89 days (P < .001). There was no change in 30-day ED visits, readmissions, or reoperations (P = .817, P = .470, and P = .643, respectively). There was no difference in ED visits, readmissions, or reoperations in SDD patients. The odds of SDD were associated with age (P < .001, odds ratio [OR] = 0.94), body mass index (P = .006, OR = 0.95), male sex (P < .001, OR = 1.83), and history of tobacco use (P < .001, OR = 1.87). Conclusions: At our institution, the COVID-19 pandemic accelerated the utilization of SDD pathways without increasing ED visits, readmissions, or reoperations.

Physiotherapy Rehabilitation Post Total Hip Replacement in the Case of Avascular Necrosis of the Femur: A Case Report.

Avascular necrosis of the femur is an irreversible and painful disorder in which the epiphyseal bone suffers from ischemia necrosis owing to an interruption in blood flow to the femoral head, resulting in bone destruction. Later, it leads to osteoarthritis of the hip joint. Here, we present the case of a 35-year-old male who came with a complaint of pain on the left side of the hip region for the past 15 days. Since the patient tested positive for COVID-19, he was quarantined. An X-ray was carried out once the quarantine period was completed, which revealed avascular necrosis of the left femoral head. He was advised to have a total hip replacement and underwent the surgery. After one month, the patient started experiencing pain on the right side of the hip region. He visited the rural hospital, where an X-ray was carried out, which revealed avascular necrosis of the right femoral head. For reducing pain and improving functional independence and quality of life postoperatively, a well-planned physiotherapy protocol was incorporated, which included lower limb and pelvic floor strengthening exercises and a balance training program. The Numerical Pain Rating Scale and Harris Hip Score have been used as outcome measures to demonstrate the efficacy of the treatment.

Meeting the demands for bone allografts: Challenges during COVID-19 pandemic

Background: Bone allografts have been an integral part of orthopedic procedures such as revision hip surgery or reconstruction of large bone defects. Femoral heads and necks were harvested from living donors undergoing total hip arthroplasty (THA). They were stored fresh frozen or processed into bone chips by the Innsbruck Bone Bank. The challenge was to meet the demand for bone grafts through in-house manufacturing even during Covid-19 pandemic restrictions. Method(s): Key data from the bone bank's registry and the hospital administration between January 2019 and March 2022 were analysed with regard to collection of fresh frozen allogenic femoral heads /necks and the manufacture of bone chips and their discard. Donor suitability and release criteria were assessed in accordance with EU and national legislation. Result(s): In 1,249 primary THA surgeries 640 femoral heads and necks were harvested. In the mean 51.4% of these yielded the bulk material for bone chips manufacture. Due to Covid-19 pandemic restrictions the number of grafts retrieved was lowest in Q1 2020 and Q4 2021. The proportion of unreleased transplants remained fairly consistent at 14%, but the reasons for discard varied: technical issues were eliminated, but the increase for discard to >30% due to reasons in donor history required the revision of the questionnaire and the collaboration with the team responsible for listing diagnoses in the medical records. By 2020, the bone chip discard rate had increased to 8%. Hence modification of cleaning and gowning brought it back down to 2% . Conclusion(s): Providing high quality bone allografts is a complex task. In this context, it is important to regularly evaluate the registry data and to modify the process accordingly, thus ensuring adequate supply of allografts even in times of significant restrictions.

Overnight joint replacement surgery: a pilot Australian study.

BACKGROUND: With a stretched healthcare system and elective surgery backlog, measures to improve efficiency and decrease costs associated with surgical procedures need to be prioritized. This study compares the benefits of multi-disciplinary involvement in an enhanced recovery after surgery (ERAS) protocol-led overnight model following total hip replacement (THR) and total knee replacement (TKR). METHODS: Patients in each of two private hospitals undergoing THR or TKR were prospectively enrolled. One hospital (Overnight) was fully committed to the ERAS protocol implementation on all levels and formed the treatment group while in the other hospital (control), patients only had the anaesthetic and operative procedure as part of the ERAS protocol but did not follow the perioperative measures of the protocol. Outcomes on hospital length of stay (LOS), inpatient rehabilitation, functional outcomes, satisfaction, adverse events and readmission rates were investigated. RESULTS: Median LOS in the Overnight group was significantly smaller than in the control group (1 vs. 3 days, P < 0.0001). The Overnight group had lower rates of inpatient rehabilitation utilization (4% vs. 41.2%, P < 0.0001), similar improvements in functional hip and knee scores and no increased rate of adverse events or readmission. All patients in both groups were satisfied with their treatment. CONCLUSION: Overnight THR and TKR can safely be performed in the majority of patients, with a multi-disciplinary approach protocol and involvement of all perioperative stakeholders.

ATYPICAL PRESENTATION OF FAT EMBOLISM SYNDROME IN AN IMMUNOCOMPROMISED PATIENT

SESSION TITLE: Systemic Diseases with Deceptive Pulmonary Manifestations SESSION TYPE: Rapid Fire Case Reports PRESENTED ON: 10/18/2022 12:25 pm - 01:25 pm INTRODUCTION: Fat embolism is a syndrome that can occur during orthopedic procedures or fractures of the long bones, especially the femur and tibia. It can affect multiple organs, including the brain, skin, and lungs, causing the triad of altered mentation, petechiae, and hypoxemia. Here, we present a case of a 54-year-old woman at risk for graft versus host disease (GVHD) who presented with dyspnea a few weeks after an orthopedic procedure. Initial chest radiograph was notable for parenchymal infiltrates, and she was initially treated with antibiotics without improvement. CASE PRESENTATION: A 54-year-old woman with a history of leukemia, stem cell transplantation years ago, GVHD (skin liver, ocular, oral, joints (not lung), with clinical and cytogenetic remission underwent total hip arthroplasty. Two weeks later, she developed lethargy and dyspnea and presented to the emergency department. She was found to have an elevated WBC of x19.5 k/ul (normal 4.1-9.3k/uL) with a left upper lobe consolidation on the chest radiograph (Figure 1). She was treated empirically for pneumonia and discharged with a 7-day course of levofloxacin. Despite completing the course of antibiotics, her dyspnea worsened, and she presented to the emergency department two weeks later with worsening hypoxemia. Computed tomography (CT) of the chest showed bilateral diffuse ground-glass opacities (GGOs) with patchy consolidations in a broncho-vascular distribution (Figure 2). She was negative for COVID-19, Influenza A, B and Legionella urinary antigen. The differential diagnosis included infection and GVHD among others. She underwent bronchoalveolar lavage (BAL). The Gram stain and the culture did not suggest an infection. Pathology from BAL returned significant for reactive bronchial and squamous cells with lipid-laden macrophages. She was started on steroids. Her clinical status improved dramatically, and she was eventually discharged. At a 3-month follow-up her symptoms had improved. Her CT scan also showed significant improvement (Figure 3). DISCUSSION: Our case highlights the successful diagnosis of fat embolism in the lungs in a patient with complicated medical history. Fat embolism usually presents as ground glass opacities. However, the diagnosis was more challenging in this case due to a significant time lapse between her surgery and her presentation to the hospital. She also lacked the other common signs of fat embolism including altered mentation and skin changes. Therefore, other etiologies, such as GVHD, bacterial or viral infection were initially strongly considered. CONCLUSIONS: The diagnosis of fat embolism syndrome condition should still be suspected despite a delay from the initial surgery. Diagnosis in immunocompromised patients requires a detailed workup to rule out other etiologies. Reference #1: Johnson, M. J., & Lucas, G. L. (1996). Fat embolism syndrome. Orthopedics, 19(1), 41-49. Reference #2: Newbigin, K., Souza, C. A., Torres, C., Marchiori, E., Gupta, A., Inacio, J., … & Peña, E. (2016). Fat embolism syndrome: state-of-the-art review focused on pulmonary imaging findings. Respiratory medicine, 113, 93-100. Reference #3: Swiatek, K., Kordic, G., & Jordan, K. (2018). An Unlikely Presentation of Fat Embolism Syndrome. Chest, 154(4), 686A. DISCLOSURES: No relevant relationships by Raheel Anwar No relevant relationships by Boris Medarov

Telemedicine Technologies Selection for the Posthospital Patient Care Process after Total Hip Arthroplasty.

For many years, the importance of using telematic technologies in medicine has been growing, especially in the period of the coronavirus pandemic, when direct contact and supervision of medical personnel over the patient is difficult. The existing possibilities of modern information and communication technologies (ICTs) are not fully used. The aim of the study is to identify the telemedicine technologies that can be used in future implementation projects of the posthospital patient care process after total hip arthroplasty (THA). The literature search is reported according to PRISMA 2020. The search strategy included databases and gray literature. In total, 28 articles (EMBASE, PubMed, PEDro) and 24 records from gray literature (Google Search and Technology presentations) were included in the research. This multi-source study analyzes the possibilities of using different technologies useful in the patient care process. The conducted research resulted in defining visual and wearable types of telemedicine technologies for the original posthospital patient care process after THA. As the needs of stakeholders in the posthospital patient care process after THA differ, the awareness of appropriate technologies selection, information flow, and its management importance are prerequisites for effective posthospital patient care with the use of telemedicine technologies.

Short-Stay Arthroplasty is Not Associated With Increased Risk of 90-Day Hospital Returns.

BACKGROUND: With the removal of total hip arthroplasty (THA) and total knee arthroplasty (TKA) from the inpatient-only list, medical centers are faced with challenging transitions to outpatient surgery. We investigated if short-stay arthroplasty, defined as length of stay (LOS) <24 hours, would influence 90-day readmissions and emergency department (ED) visits at a tertiary referral center. METHODS: The institutional database was retrospectively queried for primary TKAs and THAs from July 2015 to January 2018, resulting in 2,217 patients (1,361 TKA and 856 THA). Patient demographics, including age, gender, body mass index, and American Society of Anesthesiologists score were collected. LOS, disposition, cost of care, 90-day ED visits, and readmissions were identified through the institutional database using electronic medical record data. Univariable and multivariable models were used to evaluate rates of 90-day readmissions and ED visits based on LOS <24 hours vs ≥24 hours. RESULTS: LOS <24 h was associated with significant decreases in 90-day ED visits (P = .003) and readmissions (P = .002). After controlling for potential confounding variables with a multivariable model, a significant decrease in ED visits (P = .034) remained in the THA cohort alone. Within TKA and THA cohorts, LOS <24 h was associated with lower costs (P < .001). Eighteen percent of patients with ≥24 h LOS were discharged to skilled nursing or rehabilitation facilities. CONCLUSION: In this cohort, LOS <24 hours was associated with decreased 90-day readmissions, ED visits, and costs. With the goal of minimizing costs and maintaining patient safety while efficiently using resources, outpatient and short-stay arthroplasty are valuable, feasible options in tertiary academic centers.

The combined effect of policy changes and the covid-19 pandemic on the same day discharge and complications following total hip arthroplasty: a nationwide analysis.

INTRODUCTION: As a result of the SARS-CoV-2 (COVID-19) pandemic in 2020, elective surgeries, including total joint arthroplasty (TJA), were suspended nationwide. Concurrent removal of total hip arthroplasty (THA) from the Medicare inpatient-only list posed challenges to the delivery of quality patient care with low payor cost. Therefore, the objective of this study was to compare temporal trends in patient demographics, case volumes, length of stay, and complications following elective THA in the years 2019 to 2020 in the United States. METHODS: The 2019 to 2020 ACS-NSQIP database was queried for elective THA patients. Patients Pre-COVID (2019 and 2020Q1) were compared with post-COVID (2020Q2-Q4). THA utilization, demographics, 30-day complications, and length of stay (LOS) were compared between years. Linear regression evaluated changes in case volumes over time with significance threshold of P < 0.05. RESULTS: A total of 77,797 patients underwent elective THA in 2019 (n = 43,667) and 2020 (n = 34,130), resulting in a 24.5% decline. Outpatient THA increased in 2020 (35.6%) vs. 2019 (5.7%) (P < 0.001). There was no significant difference in the volume of cases in 2019Q1 through 2019Q4 (P = 0.984). Elective THA volumes declined by 68.8% in 2020Q2, returned to pre-pandemic baseline in 2020Q3, before leveling off at 81.5% of baseline in Q4. Average LOS was significantly shorter in 2020 (1.55 days) vs. 2019 (1.78 days) (P < 0.001) and the proportion of same day discharge (SDD) increased quarterly from 2019 to 2020. There was no significant difference in the total complication rates in 2019 (6.6%) vs. 2020 (6.6%) (P = 0.831). DISCUSSION: Elective THA precipitously declined during the second quarter of 2020. The combined effect of policy changes and the COVID-19 pandemic resulted in a seven-fold increase in the number of surgeries performed in the outpatient setting in 2020. Rates of SDD doubled over the study period, despite no change in complication rates.

First Polish mobile application for patients undergoing total hip arthroplasty.

Total hip arthroplasty (THA) is one of the most frequent orthopedic procedures worldwide and its surgical volume is constantly growing. To address the patients' restricted access to healthcare resources and limited one-on-one contact with the surgeon during the COVID-19 pandemic, we created a reliable source of information for patients undergoing THA. The use of mHealth is increasing with access to modern technology in Poland. Information related to health issues is the second most common web search performed by older adults. Our project aimed to create the first Polish mobile application for THA patients: Endopedia. Endopedia was developed for the Android platform based on a survey performed among patients and a collection of frequently asked questions on patients' internet forums. The content was adapted to the elderly and visually impaired requirements. mHealth solutions should not replace one-on-one conversation, but they can provide substantial support for patients in conditions of limited information.

Polyethylene Liner Dissociation in the Early Post-Operative Period Following Total Hip Arthroplasty: A Case Report and Literature Review.

Polyethylene liner dissociation (PLD) is a rare but catastrophic complication following total hip arthroplasty (THA). When it occurs in the early postoperative period, it can be easy to miss the diagnosis. Liner dissociation has been reported previously with the Pinnacle® (DePuy), Harris-Galante® (Zimmer), and Trident® (Stryker) acetabular components. To the best of our knowledge, this is the first case reporting PLD in the G7® cup (Zimmer-Biomet). This case report, along with a review of the literature, highlights the clinical presentation, radiological imaging, treatment options, and technical tips to avoid PLD in the early postoperative period.

Abstracts SECCA 2021

The proceedings contain 24 papers. The topics discussed include: applications of 3d models in pelvis and hip surgery;intraoperative fractures of the acetabulum in total hip arthroplasty;does depression influence postoperative total hip atroplasty?;are we meeting patient's expectations after hip preserving surgery?;hip fractures during the COVID-19 pandemic: characteristics, management and outcomes;digital preoperative planning in total hip arthroplasty: our experience;emphysematous osteomyelitis of the hip: a case report;how a tripolar system helps us in revision surgery hip;clinical and radiological risk factors for revision surgery in primary total hip replacement: a study on 4,013 total hip replacements from 2000 to 2020;and peri-prosthetic Vancouver B2 post operative femoral fractures. clinical, functional and radiographic outcomes in a case series.

RAPT Scores Predict Inpatient Versus Outpatient Status and Readmission Rates After IPO Changes for Total Joint Arthroplasty: An Analysis of 12,348 Cases.

BACKGROUND: Changes to Medicare's Inpatient Only List (IPO) and factors associated with the COVID pandemic have led to more total joint arthroplasty (TJA) patients to be designated as outpatient (OP). This potentially complicates postoperative care for patients with lower functional status and poor social support. These factors make the decision between OP versus inpatient (IP) designation particularly challenging for healthcare teams. The Risk Assessment and Prediction Tool (RAPT) was designed to indicate patient risk for needing posthospital discharge to facility and considers social and functional factors. The purpose of this study is to 1) evaluate the correlation of RAPT as a clinical tool to aid decision-making regarding OP versus IP for Total Hip and Knee Arthroplasty (THA and TKA), 2) assess the impact of recent changes to the IPO and the COVID pandemic on OP TJA readmission rates, and 3) determine whether 90-day readmissions are correlated with RAPT scores after OP TJA. METHODS: We identified all elective TKA and THA patients from 2015 through 2021 in our electronic health record at our large, urban, academic health system. Fracture patients were excluded. For those patients with available RAPT scores, we determined OP and IP designations, with IP defined as those with length-of-stay 2 midnights or more. We performed subanalysis of OP between same-day and next-day discharge. RAPT scores and readmission rates were compared at time points related to changes in the IPO: before TKA removal in 2018 (period A), from 2018 until THA removal in 2020 (Period B), and after January 1, 2020, inclusive of impact from the COVID pandemic (Period C). RESULTS: Reviewed were 11,819 elective TKAs and 10,212 elective THAs. RAPT scores were available for 6,759 TKA patients and 5,589 THA patients. For both TKA and THA, RAPT scores between IP, same-day, and next-day discharged OP were significantly different across all time periods (P < .001). The percentage of OP designation increased across all time periods for TKA and THA. Over these same time periods, mean RAPT scores decreased significantly for both OP TKA and OP THA (P < .01). Concurrent with these changes were significant increases in OP THA 90-day readmission rates across Periods A and B (P = .010) as well as A and C (P = .006). Readmitted OP TKA had significantly lower RAPT scores than OP TKA without readmission during Period B (P < .001). Readmitted OP THA had significantly lower RAPT scores than those without readmission for all periods (P < .05). To facilitate clinical utility, median RAPT scores were also analyzed, and showed that RAPT scores for OP THA patients with readmission were 1 to 2 points lower for all time periods. CONCLUSION: RAPT scores correlate with IP versus OP status for both TKA and THA and vary significantly with same-day versus next-day discharge. OP TJA RAPT scores may also help predict readmission, and counsel some patients away from OP surgery. Average RAPT scores of 10, 9, and 8 appeared to be separators for same day, next day, and inpatient stay. Changes to the IPO and COVID pandemic correlate with decrease in RAPT scores for both TKA and THA patients within all designations. In addition, a shift toward lower RAPT for OP TJA correlates with increased 90-day readmission rates for OP TJA. Taken together, these results suggest that patients with poorer function and worse social support systems are increasingly being driven toward OP surgery by these changes, which may play a role in increasing readmission rates. Social support and functional factors should be considered for OP elective TKA and THA. Further, any OP TJA value-based payment system must account for these variables.

Aggressive Presentation and Rapid Progression of Osteonecrosis of the Femoral Head After COVID-19.

Background: We aim to report the consecutive patients diagnosed with osteonecrosis of femoral head (ONFH) following recovery from COVID-19 disease and elucidate the unique features of ONFH associated with COVID-19. Methods: Consecutive 22 patients (39 hips) recovered from COVID-19 and presented with ONFH from November 2020 to October 2021 were included. All the patients received corticosteroids as a supportive treatment during COVID-19. Patients were classified into two types based on the type of presentation, namely classic ONFH and rapidly destructive coxarthrosis (RDC) depending on radiographs, MRI, inflammatory markers and hip aspiration findings. Harris hip score was used to evaluate the functional outcome before and after treatment. Results: The mean time to diagnose of ONFH from the onset of hip symptoms was 39.3 days (range 10-90 days). The average duration of onset of hip symptoms after COVID 19 infection was 7.5 months (range 3 - 11 months). The average cumulative dose of methylprednisolone equivalent was 811 mg (range 200-2100 mg) and the average duration of steroid intake was 2.8 weeks. There was significant elevation in the inflammatory markers in RDC group compared to classic ONFH (p < 0.05). The Harris hip score improved from 63.6 ± 23.2 at presentation to 82.6 ± 9.6 after treatment (p < 0.05). Three patients had features of RDC. Among the three patients with RDC, two patients had rapid progression of ONFH and underwent total hip arthroplasty (THA). The third patient is awaiting a THA. Conclusion: ONFH after COVID-19 can have a varied presentation. While the most common presentation is like classical ONFH, some patients can have an acute and aggressive presentation with rapid destruction. They have features like elevated serological markers and extensive periarticular bone and soft tissue edema. A low cumulative dose of steroids in our patients suggests that the COVID-19-associated vasculitis may play a role in the pathogenesis of ONFH.