The effect of fixation type on periprosthetic fractures in high-risk patients who have osteoporosis undergoing total joint arthroplasty.

Introduction: Minimizing the burden of periprosthetic fractures (PFF) following total joint arthroplasty (TJA) with regard to morbidity and mortality remains an outcome of interest. Patient and surgical risk factors, including osteoporosis and fixation type, have not truly been optimized in patients undergoing TJA as a means to reduce the risk of PFF. As such, we examined: (1) What percentage of patients who underwent THA and total knee arthroplasty (TKA) met the criteria for osteoporosis screening? (2) How did the 5-year rate of PFF and fragility fracture differ in the high-risk and low-risk groups for osteoporosis between the cemented and cementless cohorts? (3) What percentage of the aforementioned patients received a dual x-ray absorptiometry (DEXA) scan before THA or TKA? Methods: We queried an all-payer, national database from April 1, 2016 to December 31, 2021, to identify high-risk and low-risk patients who underwent TJA with a cementless or cemented fixation. High-risk patients met at least one of the following criteria: men at least 70 years old, women at least 65 years old, or patients at least 60 years old who have the following: tobacco use, alcohol abuse, body mass index <18.5, prior fragility fracture, chronic systemic corticosteroids, or genetic condition affecting sex hormones or bone mineral density. Exclusion criteria were a diagnosis of malignancy, high-energy events (motor vehicle collision), those who underwent TJA indicated for fracture, patients less than 50 years old, those who had a prior diagnosis of or treatment for osteoporosis, and a minimum follow-up of less than 2 years. Results: There were 384,783 patients (67.1 %) who underwent cementless TKA and 67,774 patients (11.8 %) who underwent cementless TKA who were considered high risk. Additionally, there were 62,505 patients (10.9 %) who underwent cemented THA and 58,667 patients (10.2 %) who underwent cementless THA and were considered high risk. The cementless cohort had a 5-year periprosthetic fracture risk following TKA of 7.8 % (95 % CI, 5.56 to 10.98) in comparison to 4.30 % in the cemented cohort (85 % CI, 3.98 to 4.65), P < 0.0001. The high-risk cementless cohort had a 5-year periprosthetic fracture risk following THA of 7.9 % (95 % confidence interval (CI), 6.87 to 9.19) in comparison to 7.78 % in the cemented cohort (85 % CI, 6.77 to 8.94), P < 0.0001. Conclusion: There is an increased risk of PFF at 5 years following TKA in patients at high risk for osteoporosis undergoing cementless fixation in comparison to cemented fixation. There is an increased risk of PFF at 5 years following THA in patients at high risk for osteoporosis for both cementless fixation and cemented fixation, but no clinically meaningful difference between the two groups. Addressing the shortcomings of the underutilization of bone density scans and better selecting appropriate patients for TJA based on bone quality and fracture risk can help expedite the process of improving the current state of practice.

Chronic Oral Corticosteroid Use and 10-Year Incidence of Major Complications Following Total Knee Arthroplasty.

BACKGROUND: Oral corticosteroids are the primary treatment for several autoimmune conditions. The risk of long-term implant, bone health, and infectious-related complications in patients taking chronic oral corticosteroids before total knee arthroplasty (TKA) is unknown. We compared the 10-year cumulative incidence of revision, periprosthetic joint infection (PJI), fragility fracture (FF), and periprosthetic fracture following TKA in patients who had and did not have preoperative chronic oral corticosteroid use. METHODS: A retrospective cohort analysis was conducted using a national database. Primary TKA patients who had chronic preoperative oral corticosteroid use were identified using Current Procedural Terminology and International Classification of Disease 9 and 10 codes. Exclusion criteria included malignancy, osteoporosis treatment, trauma, and < 2-year follow-up. Primary outcomes were 10-year cumulative incidence and hazard ratios (HRs) of all-cause revision (ACR), aseptic revision, PJI, FF, and periprosthetic fracture. A Kaplan-Meier analysis and a multivariable Cox proportional hazards model were utilized. Overall, 611,596 patients were identified, and 5,217 (0.85%) were prescribed chronic corticosteroids. There were 10,000 control patients randomly sampled for analysis. RESULTS: Corticosteroid patients had significantly higher 10-year HR of FF (HR; 95% confidence interval); P value (1.47; 1.34 to 1.62; P < .001)], ACR (1.21; 1.05 to 1.40; P = .009), and PJI (1.30; 1.01 to 1.69; P = .045) when compared to the control. CONCLUSIONS: Patients prescribed preoperative chronic oral corticosteroids had higher risks of ACR, PJI, and FF within 10 years following TKA compared to patients not taking corticosteroids. This information can be used by surgeons during preoperative counseling to educate this high-risk patient population about their increased risk of postoperative complications.

Trend of using cementless total knee arthroplasty: a nationwide analysis from 2015 to 2021.

BACKGROUND: Modern cementless total knee arthroplasty (TKA) fixation has shown comparable long-term outcomes to cemented TKA, but the trend of using cementless TKA remains unclear. This study aimed to investigate the trend of using cementless TKA based on a national database. METHODS: The patients undergoing cementless TKA between 2015 and 2021 were retrospectively extracted from the PearlDiver (Mariner dataset) Database. The annual percentage of cementless TKA was calculated using the following formula: annual number of cementless TKA/annual number of TKA. The trend of the number of patients undergoing cementless TKA was created according to a compounded annual growth rate (CAGR) calculation of annual percentages. Patient age, comorbidity, region, insurance type, etc., were also investigated. Differences were considered statistically significant at P < 0.05. RESULTS: Of the 574,848 patients who received TKA, 546,731 (95%) underwent cemented fixation and 28,117 (5%) underwent cementless fixation. From 2015 to 2021, the use of cementless TKA significantly increased by 242% from 3 to 9% (compounded annual growth rate (CAGR): + 20%; P < 0.05). From 2015 to 2021, we observed a CAGR greater than 15% for all age groups (< 50, 50-59, 60-69, 70-74, 75 +), insurance types (cash, commercial, government, Medicare, Medicaid), regions (Midwest, Northeast, South, West), sex (male and female), and certain comorbidities (osteoporosis, diabetes mellitus, tobacco use, underweight (BMI < 18.5), rheumatoid arthritis) (P < 0.05 for all). Patients undergoing TKA with chronic kidney disease, prior fragility fractures, and dementia demonstrated a CAGR of + 9%-13% from 2015 to 2021 (P < 0.05). CONCLUSION: From 2015 to 2021, the use of cementless TKA saw a dramatic increase in all patient populations. However, there is still no consensus on when to cement and in whom. Clinical practice guidelines are needed to ensure safe and effective use of cementless fixation.

Risk of revision total knee arthroplasty for patients with prior bariatric surgery or class III obesity.

BACKGROUND: Bariatric surgery (BS) is indicated for select class III obesity patients undergoing total knee arthroplasty (TKA) to reduce obesity-related complications. This study assessed the effect of BS on TKA revision rates compared to the general population and class III obesity patients without a history of BS. METHODS: A national database identified patients who had primary TKA. They were divided into two groups: those with BS prior to TKA and those without. Patients without BS formed two control groups, a matched general population, and a matched class III obese cohort. The BS group was matched with controls based on age, Charlson Comorbidity Index (CCI), gender, and diabetes mellitus. Revision rates were analyzed using Kaplan-Meier survival analysis and hazard ratios (HR), calculated using Cox proportional hazard modeling. RESULTS: 14,292 BS patients were compared to 57,006 matched general population controls, and 19,504 BS patients were compared to 77,846 matched class III obesity control patients. BS patients had a higher risk of 5-year all-cause revision (HR: 1.13; P = 0.014) and revision due to periprosthetic fracture (HR: 1.39; P < 0.001) compared to the general population. Compared to class III obesity controls, BS patients had a lower risk of 5-year revision due to prosthetic joint infection (HR: 0.77; P = 0.001), with no difference in all-cause revision (P = 0.362). CONCLUSION: BS does not reduce all-cause TKA revision risk compared to the general or matched class III obesity population. However, it lowers the risk of revision due to prosthetic joint infection when compared to patients with class III obesity. LEVEL OF EVIDENCE: IV.

No Difference in Revision Rates up to 10 years Following Total Hip Arthroplasty in Patients Who Had Prior Bariatric Surgery When Compared to Patients Who Had Class III Obesity: A Propensity Matched Analysis.

BACKGROUND: There is no clear research showcasing bariatric surgery's (BS's) impact on long-term surgical complications following total hip arthroplasty (THA). Therefore, this study compared the 10-year cumulative incidence and risk of revision following THA in patients who underwent BS when compared to the general population and class III obesity patients who did not undergo BS. METHODS: Patients who underwent elective THA from 2010 to 2021 were identified using an all-payer claims database. Patients who underwent BS prior to THA were separately matched to a control of the general population and those who had class III obesity (body mass index ≥40) by age, sex, Charlson Comorbidity Index, and diabetes using a 1:4 ratio. Kaplan-Meier analyses generated 10-year cumulative incidence rates, and a Cox proportional hazard ratio (HR) model generated HRs and 95% confidence intervals (CIs). RESULTS: When compared to the general control, patients who have a history of BS had an elevated 10-year risk of all-cause revision (HR 1.31, 95% CI: 1.16 to 1.47, P < .001), prosthetic joint infection (HR: 1.62, CI: 1.30 to 2.04; P < .001), mechanical loosening (HR: 1.20, CI: 1.01 to 1.44; P = .040), and dislocation/instability (HR: 1.35, CI: 1.09 to 1.68; P = .007). There was no difference in the 10-year risk of all-cause revision or other indications for revision in the BS cohort compared to the matched class III obesity cohort (P = .142). CONCLUSIONS: Those who underwent BS before THA had comparable 10-year revision rates when compared to those who had class III obesity and higher rates compared to the general population. This suggests BS may not reduce the 10-year surgical risks associated with obesity when compared to a class III obese surgical population.

Impact of Reporting Bias, Conflict of Interest, and Funding Sources on Quality of Orthopaedic Research.

BACKGROUND: Influence of factors like reporting outcomes, conflicts of interest, and funding sources on study outcomes, particularly positive outcomes in orthopedics, remains underexplored. As transparency of partnerships in orthopaedic surgery through conflicts of interest statements has increased over the years, there has been a lack of focus on the value of these partnerships in influencing study outcomes. We aimed to investigate the associations between reporting outcomes, conflicts of interest, and sources of funding on study outcomes. METHODS: We reviewed articles published in 1 year in The Journal of Bone and Joint Surgery, The American Journal of Sports Medicine, and The Journal of Arthroplasty. The abstracts were examined for appropriate inclusion, while the authors' names, academic degrees, funding disclosures, and departmental and institutional affiliations were redacted. There were a total of 1,351 publications reviewed from January 1, 2021 to December 31, 2021. RESULTS: A significant association was found between positive outcomes and reported conflicts of interest (75% versus 25%, P < .001). Likewise, conflicts of interest showed significant association with industry-sponsored studies (88% versus 12%, P < .001) and evidence level > II (72% versus 28%, P < .001). Industry-sponsored research accounted for the highest percentage of studies involving a conflict of interest (88%) and level I studies (12%). CONCLUSIONS: Conflicts of interest are significantly associated with positive outcomes in orthopaedics. Sponsored studies were more inclined to have conflicts of interest and accounted for the majority of level I studies.

Comparison of Pneumonia and Major Complications After Total Joint Arthroplasty With Spinal Versus General Anesthesia: A Propensity-matched Cohort Analysis.

INTRODUCTION: Spinal anesthesia (SA) allows total joint arthroplasty to be done while minimizing opioids and systemic anesthetic agents compared with general anesthesia (GA). SA has been associated with shortened postoperative recovery; however, the relationship between SA, major postoperative complications, and pneumonia (PNA) remains unclear. METHODS: Patients in a large, national database who underwent total hip arthroplasty or total knee arthroplasty from 2010 to 2020 were identified. 1:1 propensity score matching was used to create matched groups of patients who underwent SA and GA. The groups were matched by age, sex, chronic obstructive pulmonary disease, smoking status, Charlson Comorbidity Index, and American Society of Anesthesiology (ASA) classification. 1:1 matching was also done among the ASA classifications as a subanalysis. RESULTS: Overall, equally matched groups of 217,267 patients who underwent SA versus GA were identified. 850 patients (0.39%) developed postoperative PNA after GA versus 544 patients (0.25%) after SA ( P < 0.001). The risk of major complications was 6,922 (3.2%) in the GA group and 5,401 (2.5%) in the SA group ( P < 0.001). Similarly, the risk of unplanned postoperative reintubation was higher (0.18% versus 0.10%, P < 0.001) and mortality was higher (0.14% versus 0.09%, P < 0.001) in the GA group than in the SA group. In ASA 1 to 3 patients, the risk of PNA was 0.08% to 0.21% higher with GA than with SA. In ASA 4 patients, the risk of PNA was 0.42% higher in SA than in GA (1.92% versus 1.5%, P < 0.001) and the mortality rate was nearly doubled in GA than in SA (1.46% versus 0.77%, P = 0.017). DISCUSSION: Overall, GA was associated with a small but markedly higher rate of major complications, mortality, and PNA than SA in patients undergoing total joint arthroplasty when matching for differences in comorbidities. ASA 4 patients experienced the greatest increase in absolute risk of mortality with GA versus SA.

Hydroxyapatite-Coated Femoral Stems in Primary Total Hip Arthroplasty: An Updated Meta-Analysis.

BACKGROUND: Most primary total hip arthroplasties (THAs) performed in the United States utilize cementless fixation with porous or hydroxyapatite (HA) coating. A previous meta-analysis comparing HA-coated versus non-HA-coated stems in primary THA published in 2013 found no significant difference between the 2. However, an updated analysis of the current literature is needed to assess the potential benefit of HA-coated stems in primary THA. METHODS: Various libraries were searched through May 2022 according to Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. Studies included were randomized controlled trials comparing HA-coated femoral stems to non-HA-coated stems in primary THA. Outcomes included Harris Hip Score (HHS), endosteal bone formation, radiolucent lines, linear wear rate, revision for aseptic loosening, thigh pain, and heterotopic ossification. RESULTS: There were significantly fewer revisions for aseptic loosening (P = .004) and decreased postoperative thigh pain (P = .03) for patients who have with HA-coated stems. There was no significant difference in HHS (P = .20), endosteal bone formation (P = .96), radiolucent lines (P = .75), linear wear rate (P = .41), or heterotopic ossification (P = .71) between HA-coated and non-HA-coated stems. CONCLUSION: We found that HA-coated femoral stems in primary THA led to significantly fewer stem revisions for aseptic loosening and less postoperative thigh pain compared to non-HA-coated stems. These findings suggest HA-coated femoral stems should be preferred over non-HA-coated femoral stems in primary THA.

Osteoporosis and Total Knee Arthroplasty: Higher 5-Year Implant-Related Complications.

BACKGROUND: The risk of revision surgery in patients who have osteoporosis after total knee arthroplasty (TKA) is understudied. Our aim was to compare the 5-year cumulative risk of revision surgery after TKA in patients who have preoperative osteoporosis. METHODS: A national administrative claims database was queried for patients undergoing primary TKA from 2010 to 2021. There were 418,054 patients included, and 41,760 (10%) had osteoporosis. The 5-year incidence of revision surgery was examined for all-causes, periprosthetic fracture (PPF), aseptic loosening, and periprosthetic joint infection (PJI). A multivariable analysis was conducted using Cox proportional hazards models. Hazards ratios (HRs) were reported with 95% confidence intervals (CIs). RESULTS: The 5-year rate of all-cause revision surgery was higher for patients who had osteoporosis (HR 1.1, 95% CI: 1.0 to 1.2), however, the highest risk of revision surgery was seen for PPF (HR 1.8, 95% CI: 1.6 to 2.1). Patients who had osteoporosis also had elevated risk of revision surgery for PJI (HR 1.2, 95% CI: 1.1 to 1.3) and aseptic loosening (HR 1.2, 95% CI: 1.1 to 1.3). Osteoporosis was independently associated with PJI and aseptic loosening at a higher rate in obese patients. CONCLUSIONS: In unadjusted survival analysis, those who had osteoporosis have a marginally lower risk of all-cause revision surgery. However, after controlling for age, sex and comorbidities, patients who had osteoporosis have a nearly 2-fold increased risk of 5-year revision for PPF after TKA, and mildly increased risk of revision for all causes, aseptic loosening, and PJI. Obesity may also modulate this association. Future studies should determine the extent to which treatment of osteoporosis modifies these postoperative outcomes.

Previous external beam radiation therapy for pelvic malignancy increases complications of total hip arthroplasty.

INTRODUCTION: External beam radiation therapy (EBRT) has known effects on bone health. No large database studies have looked at the effects of pelvic EBRT on total hip arthroplasty (THA) outcomes. The purpose of this study was to evaluate 90-day and long-term (>2 years) complication rates following THA in patients with a history of pelvic malignancy and EBRT. METHODS: Patients were retrospectively identified using a national insurance claims database. Subjects who underwent THA for osteoarthritis or avascular necrosis were included if they had at least 2-year follow-up and were stratified into 3 cohorts: (1) prior pelvic malignancy diagnosis (prostate, cervical, uterine, ovarian, or rectal) and EBRT (Group A); (2) prior malignancy diagnosis but no EBRT (Group B); and (3) neither prior malignancy diagnosis nor EBRT (Group C). Univariate and multivariate analyses were conducted to evaluate for an association between prior EBRT and the incidence of 90-day and 2-year complication rates using chi-square, student t-tests, and logistic regression analyses where appropriate. RESULTS: 671,554 patients met the inclusion criteria. Group A had higher odds of all-cause revision, septic revision, and loosening with revision after 2 years when compared to Group C and Group B (p < 0.001). Group A subjects had higher rates of 90-day deep vein thrombosis, sepsis, and stroke (p < 0.001) than groups B and C. CONCLUSIONS: Prior EBRT for pelvic malignancy was associated with significantly increased rates of all-cause revision, septic revision, and loosening as well as 90-day medical complications.

Higher revision rates in patients with preoperative contralateral pes planovalgus deformity following total knee arthroplasty.

PURPOSE: The purpose of this study was to compare the incidence of revision in those with pes planovalgus deformity to those without using a large national database. Given the reciprocal changes in lower extremity alignment associated with planovalgus foot deformity, it has been suggested that patients with this deformity has worse outcomes following total knee arthroplasty (TKA). METHODS: A retrospective cohort analysis of patients undergoing elective TKA was conducted using the PearlDiver database. Patients were stratified into three cohorts: those without pes planovalgus, patients with ipsilateral or bilateral pes planovalgus relative to the TKA, and patients with contralateral pes planovalgus. Patients with prior foot reconstructive surgery were excluded. The cohorts were each matched to those without pes planovalgus. Bivariate analysis was performed comparing 90-day medical complications and 2- and 4-year revisions following TKA. An adjusted number needed to be exposed for one additional person to be harmed (NNEH) was calculated using the adjusted odds ratio (OR) and unexposed event rate. RESULTS: Following matched analysis, those with contralateral pes planovalgus had similar odds (OR 3.41; 95% CI 0.93-12.54; p = n.s.) for aseptic revision within 2 years but significantly higher odds (OR 3.35; 95% CI 1.08-10.41; p = 0.03) within 4 years when compared to those without a pes planovalgus deformity. Within 4 years, there was no significant difference in the incidence of aseptic revision (p = n.s.) in patients with ipsilateral/bilateral pes planovalgus. No patients in any cohort underwent septic revision within 4 years of TKA. CONCLUSION: This study found that patients with contralateral pes planovalgus deformity had higher odds of aseptic revision within 4 years following primary TKA in a national database, suggesting that the change in gait kinematics associated with this deformity could possibly be associated with increased revision rates. LEVEL OF EVIDENCE: Level III.

Can Hip and Knee Arthroplasty Surgeons Help Address the Osteoporosis Epidemic?

BACKGROUND: Osteoporosis is a known, modifiable risk factor for lower extremity periprosthetic fractures. Unfortunately, a high percentage of patients at risk of osteoporosis who undergo THA or TKA do not receive routine screening and treatment for osteoporosis, but there is insufficient information determining the proportion of patients undergoing THA and TKA who should be screened and their implant-related complications. QUESTIONS/PURPOSES: (1) What proportion of patients in a large database who underwent THA or TKA met the criteria for osteoporosis screening? (2) What proportion of these patients received a dual-energy x-ray absorptiometry (DEXA) study before arthroplasty? (3) What was the 5-year cumulative incidence of fragility fracture or periprosthetic fracture after arthroplasty of those at high risk compared with those at low risk of osteoporosis? METHODS: Between January 2010 and October 2021, 710,097 and 1,353,218 patients who underwent THA and TKA, respectively, were captured in the Mariner dataset of the PearlDiver database. We used this dataset because it longitudinally tracks patients across a variety of insurance providers throughout the United States to provide generalizable data. Patients at least 50 years old with at least 2 years of follow-up were included, and patients with a diagnosis of malignancy and fracture-indicated total joint arthroplasty were excluded. Based on this initial criterion, 60% (425,005) of THAs and 66% (897,664) of TKAs were eligible. A further 11% (44,739) of THAs and 11% (102,463) of TKAs were excluded because of a prior diagnosis of or treatment for osteoporosis, leaving 54% (380,266) of THAs and 59% (795,201) of TKAs for analysis. Patients at high risk of osteoporosis were filtered using demographic and comorbidity information provided by the database and defined by national guidelines. The proportion of patients at high risk of osteoporosis who underwent osteoporosis screening via DEXA scan within 3 years was observed, and the 5-year cumulative incidence of periprosthetic fractures and fragility fracture was compared between the high-risk and low-risk cohorts. RESULTS: In total, 53% (201,450) and 55% (439,982) of patients who underwent THA and TKA, respectively, were considered at high risk of osteoporosis. Of these patients, 12% (24,898 of 201,450) and 13% (57,022 of 439,982) of patients who underwent THA and TKA, respectively, received a preoperative DEXA scan. Within 5 years, patients at high risk of osteoporosis undergoing THA and TKA had a higher cumulative incidence of fragility fractures (THA: HR 2.1 [95% CI 1.9 to 2.2]; TKA: HR 1.8 [95% CI 1.7 to 1.9]) and periprosthetic fractures (THA: HR 1.7 [95% CI 1.5 to 1.8]; TKA: HR 1.6 [95% CI 1.4 to 1.7]) than those at low risk (p < 0.001 for all). CONCLUSION: We attribute the higher rates of fragility and periprosthetic fractures in those at high risk compared with those at low risk to an occult diagnosis of osteoporosis. Hip and knee arthroplasty surgeons can help reduce the incidence and burden of these osteoporosis-related complications by initiating screening and subsequently referring patients to bone health specialists for treatment. Future studies might investigate the proportion of osteoporosis in patients at high risk of having the condition, develop and evaluate practical bone health screening and treatment algorithms for hip and knee arthroplasty surgeons, and observe the cost-effectiveness of implementing these algorithms. LEVEL OF EVIDENCE: Level III, therapeutic study.

The impact of prior fragility fractures on long-term periprosthetic fracture risk following total knee arthroplasty.

The study found that patients undergoing total knee arthroplasty with prior fragility fracture had increased risk of subsequent fragility fracture and periprosthetic fracture within 8 years postoperatively when compared to those without a prior history. However, these patients were not at increased risk for all-cause revision within this period. PURPOSE: The aim of this study was to characterize the association of prior FFs on long-term risk of secondary fragility fracture (FF), periprosthetic fracture (PPF), and revision TKA. METHODS: Patients at least 50 years of age who underwent elective TKA were identified in the PearlDiver Database. Patients were stratified based on whether they sustained a FF within 3 years prior to TKA (7410 patients) or not (712,954 patients). Demographics and comorbidities were collected. Kaplan Meier analysis was used to observe the cumulative incidence of all-cause revision, PPF, and secondary FF within 8 years of TKA. Cox Proportional hazard ratio analysis was used to statistically compare the risk. RESULTS: In total, 1.0% of patients had a FF within three years of TKA. Of these patients, only 22.6% and 10.9% had a coded diagnosis of osteoporosis and osteopenia, respectively, at time of TKA. The 8-year cumulative incidence of secondary FF and periprosthetic fracture was significantly higher in those with a prior FF (27.5% secondary FF and 1.9% PPF) when compared to those without (9.1% secondary FF and 0.7% PPF). After adjusting for covariates, patients with a recent FF had significantly higher risks of secondary FF (HR 2.73; p < 0.001) and periprosthetic fracture (HR 1.86; p < 0.001) than those without a recent FF. CONCLUSIONS: Recent FF before TKA is associated with increased risk for additional FF and PPF within 8 years following TKA. Surgeons should ensure appropriate management of fragility fracture is undertaken prior to TKA to minimize fracture risk, and if not, be vigilant to identify patients with prior FF or other bone health risk factors who may have undocumented osteoporosis.

Prediction of Non-Home Discharge Following Total Hip Arthroplasty in Geriatric Patients.

Introduction: The majority of total hip arthroplasty (THA) patients are discharged home postoperatively, however, many still require continued medical care. We aimed to identify important characteristics that predict nonhome discharge in geriatric patients undergoing THA using machine learning. We hypothesize that our analyses will identify variables associated with decreased functional status and overall health to be predictive of non-home discharge. Materials and Methods: Elective, unilateral, THA patients above 65 years of age were isolated in the NSQIP database from 2018-2020. Demographic, pre-operative, and intraoperative variables were analyzed. After splitting the data into training (75%) and validation (25%) data sets, various machine learning models were used to predict non-home discharge. The model with the best area under the curve (AUC) was further assessed to identify the most important variables. Results: In total, 19,840 geriatric patients undergoing THA were included in the final analyses, of which 5194 (26.2%) were discharged to a non-home setting. The RF model performed the best and identified age above 78 years (OR: 1.08 [1.07, 1.09], P < .0001), as the most important variable when predicting non-home discharge in geriatric patients with THA, followed by severe American Society of Anesthesiologists grade (OR: 1.94 [1.80, 2.10], P < .0001), operation time (OR: 1.01 [1.00, 1.02], P < .0001), anemia (OR: 2.20 [1.87, 2.58], P < .0001), and general anesthesia (OR: 1.64 [1.52, 1.79], P < .0001). Each of these variables was also significant in MLR analysis. The RF model displayed good discrimination with AUC = .831. Discussion: The RF model revealed clinically important variables for assessing discharge disposition in geriatric patients undergoing THA, with the five most important factors being older age, severe ASA grade, longer operation time, anemia, and general anesthesia. Conclusions: With the rising emphasis on patient-centered care, incorporating models such as these may allow for preoperative risk factor mitigation and reductions in healthcare expenditure.

Prediction of suitable outpatient candidates following revision total knee arthroplasty using machine learning.

Aims: To identify variables independently associated with same-day discharge (SDD) of patients following revision total knee arthroplasty (rTKA) and to develop machine learning algorithms to predict suitable candidates for outpatient rTKA. Methods: Data were obtained from the American College of Surgeons National Quality Improvement Programme (ACS-NSQIP) database from the years 2018 to 2020. Patients with elective, unilateral rTKA procedures and a total hospital length of stay between zero and four days were included. Demographic, preoperative, and intraoperative variables were analyzed. A multivariable logistic regression (MLR) model and various machine learning techniques were compared using area under the curve (AUC), calibration, and decision curve analysis. Important and significant variables were identified from the models. Results: Of the 5,600 patients included in this study, 342 (6.1%) underwent SDD. The random forest (RF) model performed the best overall, with an internally validated AUC of 0.810. The ten crucial factors favoring SDD in the RF model include operating time, anaesthesia type, age, BMI, American Society of Anesthesiologists grade, race, history of diabetes, rTKA type, sex, and smoking status. Eight of these variables were also found to be significant in the MLR model. Conclusion: The RF model displayed excellent accuracy and identified clinically important variables for determining candidates for SDD following rTKA. Machine learning techniques such as RF will allow clinicians to accurately risk-stratify their patients preoperatively, in order to optimize resources and improve patient outcomes.

10-Year Cumulative Incidence and Indications for Revision Total Knee Arthroplasty Among Patients Who Have Sickle Cell Disease.

BACKGROUND: Literature regarding total knee arthroplasty (TKA) outcomes in sickle cell disease (SCD) is limited. Moreover, 10-year survivorship of SCD implants is unknown. This study aimed to observe 10-year cumulative incidence and indications for revision TKA in patients who did and did not have SCD. METHODS: Patients who underwent primary TKA were identified using a large national database. The SCD patients were matched by age, sex, and a comorbidity index to a control cohort in a 1:4 ratio. The 10-year cumulative incidence rates were determined using Kaplan-Meier survival analyses. Multivariable analyses were conducted using Cox proportional hazard modeling. Chi-squared analyses were conducted to compare indications for revision between cohorts. In total, 1,010 SCD patients were identified, 100,000 patients included in the unmatched control, and 4,020 patients included in the matched control. RESULTS: Compared to the unmatched control cohort, SCD patients exhibited higher 10-year all-cause revision (HR: 1.86; P < .001) with higher proportions of revisions for periprosthetic joint infection (PJI) (P < .001), aseptic loosening (P < .001), and hematoma (P < .001). Compared to the matched control, SCD patients had higher 10-year all-cause revision (Hazard Ratio (HR): 1.39; P = .034) with a higher proportion of revisions for PJI (P = .044), aseptic loosening (P = .003), and hematoma (P = .019). CONCLUSION: Independent of other comorbidities, SCD patients are more likely to undergo revisions for PJI, aseptic loosening, and hematoma compared to patients who do not have SCD. Due to the high-risk of these complications, perioperative and postoperative surgical optimization should be enforced in SCD patients.

Trends of Venous Thromboembolism After Total Hip Arthroplasty in the United States: Analysis From 2011 to 2019.

BACKGROUND: In 2011, the American Academy of Orthopaedic Surgeons released a Clinical Practice Guideline` that recommended routine venous thromboembolism (VTE) prophylaxis after total joint arthroplasty. The purpose of this study was to examine (1) the change in the incidence of 90-day VTE, deep vein thrombosis, and pulmonary embolism, (2) the change in the utilization of antithrombotic agents; and (3) the change in the economic burden associated with VTE after total hip arthroplasty (THA) from 2011 to 2019. METHODS: National, administrative claims data from 2011 to 2019 were used to identify patients who underwent primary THA for osteoarthritis. Exclusions entailed liver pathology, coagulopathy, malignancy, or those on prior prescribed blood thinners before THA. Multivariable regression was used, controlling for age and Charlson Comorbidity Index for all years, with 2011 as the reference year. RESULTS: From 2011 to 2019, there was a significant reduction in 90-day VTE rates after THA, with a significant reduction in deep vein thrombosis and pulmonary embolism during this time frame as well. Of the antithrombotic agents prescribed after THA, the utilization of prescribed aspirin significantly increased and that of nonaspirin anticoagulants significantly decreased. Among nonaspirin anticoagulants, the utilization of direct factor Xa inhibitors and direct thrombin inhibitors significantly increased. The added reimbursements associated with VTE after THA significantly decreased during this period. CONCLUSION: Since 2011, the incidence and economic burden associated with VTE after THA have significantly declined. In addition, there has been an increase in prescription aspirin and direct oral anticoagulants. LEVEL OF EVIDENCE: Therapeutic, III.

Temporal trends in the rate of complications and prolonged length of stay relative to body mass index in patients undergoing total knee arthroplasty from 2012 to 2020.

BACKGROUND: Elevated body mass index (BMI) is a risk factor for complications following total knee arthroplasty (TKA). Thus, we believe it is important to constantly re-evaluate the relationship between BMI and complication risk following TKA. METHOD: Patients undergoing primary TKA were identified in a national database from 2012-2020. Rates of major complications, minor complications, and length of stay (LOS) greater than 2 days were calculated. The prevalence of postoperative outcomes were calculated per unit of BMI and then multiplied by a factor of 10^2 or 10^3 in order to create adjusted-BMI (aBMI). To isolate the effect of aBMI on postoperative outcomes, changes over time were analyzed using linear regression analysis controlling for age, sex, American Society of Anesthesiology (ASA) classification and smoking status. RESULTS: 365,333 patients were included. Mean BMI 33 ± 6.8. 10,616 (2.9%) of patients had a major postoperative complication, 9,345 (2.6%) minor complications, 3,277 (0.9%) had a deep or superficial surgical site infection (SSI). 133,563 (37%) of patients had LOS > 2 days. From 2012-2020, the ratio of major complications to aBMI decreased significantly by an average of -2.7% per year. The ratio of patients with LOS > 2 days to aBMI decreased significantly by -27% per year. The ratio of SSI to aBMI increased significantly by 10.8% per year. CONCLUSIONS: From 2012 to 2020, the ratio of major complications and extended LOS following TKA as a function of BMI has decreased significantly, while the ratio of SSI as a function of BMI has doubled.