Role of femoral head material on readmission and mortality rates following elective primary total hip arthroplasty in Medicare patients.

INTRODUCTION: The role of different femoral head materials for total hip arthroplasty (THA) has been widely studied in the context of wear properties and corrosion. Cobalt chrome (CoCr) femoral heads are commonly used as a standard of comparison to other materials such as ceramic and oxidized zirconium (OxZi). This study aims to evaluate the impact of femoral head material on clinical outcomes in elective primary THA patients. METHODS: Retrospective analysis of THA patients within the Medicare claims database between October 2017 and September 2020 using diagnosis-related group codes was conducted. Information collected included sex, age, Charlson Comorbidity Index, and femoral head type. Patients with CoCr femoral heads were compared against patients with either OxZi or ceramic femoral heads using 1:1 propensity score matching. Z-testing and Chi-square analysis were used to determine between-group significance. RESULTS: In total, 112,960 elective THA patients were included, with 56,480 in OxZi or ceramic and 56,480 in CoCr. Readmission rates were lower in patients that received OxZi or ceramic femoral heads at 30-day (p < 0.0001), 60-day (p < 0.0001), and 90-day postoperatively (p < 0.0001) compared to CoCr. Mortality rates were also lower in patients that received OxZi or ceramic femoral heads at 30-day (p = 0.004), 60-day (p = 0.018), and 90-day postoperatively (p = 0.009) compared to CoCr. CONCLUSION: CoCr femoral heads had higher rates of readmissions and mortality compared to OxZi or ceramic. Further analysis of bearing surface combinations and sub-group analyses to determine significance between-group differences is needed. LEVEL III EVIDENCE: Retrospective analysis.

Outcomes of medicaid patients undergoing TJA with previous positive urine toxicology screens.

INTRODUCTION: Previous studies have demonstrated that patients with positive preoperative urine toxicology (utox) screens prior to total joint arthroplasty (TJA) have higher readmission rates, greater complication rates, and longer hospital stays compared to patients with negative screens. The aim of this study was to investigate the effect of postponing surgery for patients with positive preoperative utox in the Medicaid population. METHODS: This retrospective, observational study reviewed the Medicaid ambulatory database at a large, academic orthopedic specialty hospital for patients with a utox screen prior to TJA from 2012 to 2020. Patients were categorized into three groups: (1) controls with negative preoperative utox or a utox consistent with prescription medications (Utox-) with TJA completed as scheduled; (2) positive preoperative utox with TJA rescheduled and surgery completed on a later date (R-utox+); (3) positive preoperative utox inconsistent with prescription medications with TJA completed as scheduled (S-utox+). Primary outcomes included mortality, 90-day readmission rate, complication rate, and length of stay. RESULTS: Of the 300 records reviewed, 185 did not meet inclusion criteria. The remaining 115 patients included 80 (69.6%) Utox-, 5 (6.3%) R-utox+, and 30 (37.5%) S-utox+. Mean follow-up time was 49.6 months. Hospital stays trended longer in the Utox- group (3.7 ± 2.0 days vs. 3.1 ± 1.6 S-utox+ vs.2.5 ± 0.4 R-utox+, p = 0.20). Compared to the R-utox+group, the S-utox+ group trended toward lower home discharge rates (p = 0.20), higher in-hospital complication rates (p = 0.85), and more all-cause 90-day emergency department visits (p = 0.57). There were no differences in postoperative opioid utilization between groups (p = 0.319). Duration of postoperative narcotic use trended toward being longer in the Utox- patients (820.7 ± 1073.8 days vs. 684.6 ± 1491.8 S-utox+ vs. 585.1 ± 948.3 R-utox+, p = 0.585). Surgical time (p = 0.045) and revision rates (p = 0.72) trended toward being higher in the S-utox+ group. CONCLUSIONS: Medicaid patients with positive preoperative utox who had surgeries postponed trended towards shorter hospital stays and greater home discharge rates. Larger studies should be conducted to analyze the implications of a positive preoperative utox on risk profiles and outcomes following TJA in the Medicaid population. Study design Retrospective cohort study.

Larger operating rooms have better air quality than smaller rooms in primary total knee arthroplasty.

INTRODUCTION: Operating room air quality can be affected by several factors including temperature, humidity, and airborne particle burden. Our study examines the role of operating room (OR) size on air quality and airborne particle (ABP) count in primary total knee arthroplasty (TKA). MATERIALS AND METHODS: We analyzed all primary, elective TKAs performed within two ORs measuring 278 sq ft. (small) and 501 sq ft. (large) at a single academic institution in the United States from April 2019 to June 2020. Intraoperative measurements of temperature, humidity, and ABP count were recorded. p values were calculated using t test for continuous variables and chi-square for categorical values. RESULTS: 91 primary TKA cases were included in the study, with 21 (23.1%) in the small OR and 70 (76.9%) in the large OR. Between-groups comparisons revealed significant differences in relative humidity (small OR 38.5% ± 7.24% vs. large OR 44.4% ± 8.01%, p = 0.002). Significant percent decreases in ABP rates for particles measuring 2.5 µm (- 43.9%, p = 0.007) and 5.0 µm (- 69.0%, p = 0.0024) were found in the large OR. Total time spent in the OR was not significantly different between the two groups (small OR 153.09 ± 22.3 vs. large OR 173 ± 44.6, p = 0.05). CONCLUSIONS: Although total time spent in the room did not differ between the large and small OR, there were significant differences in humidity and ABP rates for particles measuring 2.5 µm and 5.0 µm, suggesting the filtration system encounters less particle burden in larger rooms. Larger studies are required to determine the impact this may have on OR sterility and infection rates.

Outcomes After Arthroscopic Revision Bankart Repair: An Updated Systematic Review of Recent Literature.

PURPOSE: To provide an update of recent literature with a specialized focus on clinical outcomes following arthroscopic revision Bankart repair (ARBR) by performing a systematic review of all available literature published between 2013 and 2020. METHODS: A literature search reporting clinical outcomes after ARBR was performed. Criteria for inclusion consisted of original studies; Level of Evidence of I-IV; studies focusing on clinical outcomes after ARBR published between January 1, 2013, and January 4, 2021; studies reporting recurrent dislocation or instability rate after ARBR; reoperation/revision following ARBR, return to sport rates following ARBR; and patient-reported outcomes. The primary outcomes of interest were failure defined as recurrent instability or dislocation, return to sport rates, and patient-reported outcomes at follow-up. RESULTS: A large proportion of patients undergoing arthroscopic revision Bankart repair were male, ranging between 67.7% and 93.8%. Failure rate and return to sports rate ranged between 6.1% and 46.8% and 25.9% and 88.3%, respectively, when patients with significant or greater than 20% glenoid bone loss was excluded. Patient-reported outcome scores, which included American Shoulder and Elbow Surgeons, Simple Shoulder Test, and visual analog scale, saw significant improvement over mean follow-up of ranging 21.64 to 60 months. CONCLUSIONS: Both the failure rate and RTS rates after ARBR had a wide range, given the heterogeneity of the studies included, which varied in patient selection criteria pertaining to patients with greater than 20% glenoid bone. Although there have been advancements in arthroscopic techniques and a trend favoring arthroscopic stabilization procedures, there is a lack of consensus in recent literature for careful patient selection criteria that would minimize failure rates and maximize RTS rates after ARBR. LEVEL OF EVIDENCE: Level IV, a systematic review of Level III-IV studies.

Impact of preoperative opioid use on patient-reported outcomes following primary total knee arthroplasty.

PURPOSE: The previous literature suggests that 25-30% of patients who undergo total knee arthroplasty (TKA) are using opioids prior to their surgery. This study aims to investigate the effect of preoperative opioid use on clinical outcomes and patient-reported outcome measures (PROMs) following TKA. METHODS: We retrospectively reviewed 329 patients who underwent primary TKA from 2019 to 2020, answered the preoperative opioid survey, and had available PROMs. Patients were stratified into two groups based on whether they were taking opioids preoperatively or not: 26 patients with preoperative opioid use (8%) and 303 patients without preoperative opioid use (92%) were identified. Demographics, clinical data, and PROMs [Forgotten Joint Score (FJS-12), Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR), and Veterans RAND-12 Physical and Mental components (VR-12 PCS and MCS)] were collected. Demographic differences were assessed with Chi-square and independent sample t-tests. Outcomes were compared using multilinear regression analysis, controlling for demographic differences. RESULTS: Preoperative opioid users had a significantly longer length-of-stay (2.74 vs. 2.10; p = 0.010), surgical time (124.65 vs. 105.69; p < 0.001), and were more likely to be African-American (38.5 vs. 14.2%; p = 0.010) compared to preoperative opioid-naive patients. Postoperative FJS-12 did not statistically differ between the two groups. While preoperative KOOS, JR scores were significantly lower for preoperative opioid users (41.10 vs. 46.63; p = 0.043), they did not significantly differ postoperatively. Preoperative VR-12 PCS did not statistically differ between the groups; however, both 3-month (33.87 vs. 38.41; p = 0.049) and 1-year (36.01 vs. 44.73; p = 0.043) scores were significantly lower for preoperative opioid users. Preoperative VR-12 MCS was significantly lower for preoperative opioid users (46.06 vs. 51.06; p = 0.049), though not statistically different postoperatively. CONCLUSION: At 8%, our study population had a lower percentage of opioid users than previously reported in the literature. Preoperative opioid users had longer operative times and length of stay compared to preoperatively opioid-naive patients. While both cohorts achieved similar clinical benefits following TKA, preoperative opioid users reported lower postoperative scores with respect to VR-12 PCS scores. LEVEL III EVIDENCE: Retrospective Cohort.

Trends of obesity rates between primary total hip arthroplasty patients and the general population from 2013 to 2020.

BACKGROUND: The prevalence of obesity in total hip arthroplasty (THA) patients has been studied in the past. However, there has not been direct comparison against obesity in the general population. This study compared yearly trends in BMI and obesity rates between patients who had undergone primary THA and those from the general patient population. METHODS: We retrospectively reviewed all patients over the age of 18 who underwent primary, elective THA and those who had an annual routine physical exam between January 2013 and December 2020 at our academic tertiary medical center. Baseline demographics were controlled in our statistical models. Significance of yearly trends was determined through a linear regression analysis. Independent samples t-test and Chi-square test were used to compare means and proportions between the two groups, respectively. RESULTS: A total of 11,250 primary THA patients and 1,039,918 annual physical exam patients were included. Average BMI for the THA group was significantly higher (P < 0.001) each year compared to the annual physicals group (APG). Higher obesity rates were observed in all obesity subgroups (all classes, and class I-III individually) for THA patients each year compared to the APG. Interestingly, while we found a significantly increasing trend in obesity for the general population (P < 0.001), BMI and obesity rates remained stable in the THA population. CONCLUSION: While our general patient population showed significant increase in BMI and obesity over time, THA patients had higher, yet stable, BMI. Further investigation is required to determine the role of risk optimization in these findings. LEVEL III EVIDENCE: Retrospective Cohort Study.

Validation of a Predictive Tool for Discharge to Rehabilitation or a Skilled Nursing Facility After TJA.

BACKGROUND: Cost excess in bundled payment models for total joint arthroplasty (TJA) is driven by discharge to rehabilitation or a skilled nursing facility (SNF). A recently published preoperative risk prediction tool showed very good internal accuracy in stratifying patients on the basis of likelihood of discharge to an SNF or rehabilitation. The purpose of the present study was to test the accuracy of this predictive tool through external validation with use of a large cohort from an outside institution. METHODS: A total of 20,294 primary unilateral total hip (48%) and knee (52%) arthroplasty cases at a tertiary health system were extracted from the institutional electronic medical record. Discharge location and the 9 preoperative variables required by the predictive model were collected. All cases were run through the model to generate risk scores for those patients, which were compared with the actual discharge locations to evaluate the cutoff originally proposed in the derivation paper. The proportion of correct classifications at this threshold was evaluated, as well as the sensitivity, specificity, positive and negative predictive values, number needed to screen, and area under the receiver operating characteristic curve (AUC), in order to determine the predictive accuracy of the model. RESULTS: A total of 3,147 (15.5%) of the patients who underwent primary, unilateral total hip or knee arthroplasty were discharged to rehabilitation or an SNF. Despite considerable differences between the present and original model derivation cohorts, predicted scores demonstrated very good accuracy (AUC, 0.734; 95% confidence interval, 0.725 to 0.744). The threshold simultaneously maximizing sensitivity and specificity was 0.1745 (sensitivity, 0.672; specificity, 0.679), essentially identical to the proposed cutoff of the original paper (0.178). The proportion of correct classifications was 0.679. Positive and negative predictive values (0.277 and 0.919, respectively) were substantially better than those of random selection based only on event prevalence (0.155 and 0.845), and the number needed to screen was 3.6 (random selection, 6.4). CONCLUSIONS: A previously published online predictive tool for discharge to rehabilitation or an SNF performed well under external validation, demonstrating a positive predictive value 79% higher and number needed to screen 56% lower than simple random selection. This tool consists of exclusively preoperative parameters that are easily collected. Based on a successful external validation, this tool merits consideration for clinical implementation because of its value for patient counseling, preoperative optimization, and discharge planning. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Comparison of Operating Room Air Quality in Primary Versus Revision Total Knee Arthroplasty.

BACKGROUND: Airborne biologic particles (ABPs) can be measured intraoperatively to evaluate operating room (OR) sterility. Particulate matter (PM) up to 2.5 microns can contain microbial species which may increase infection risk. Our study examines the differences in air quality and ABP count in primary total knee arthroplasty (TKA) and revision TKA (rTKA). METHODS: We analyzed primary and rTKAs in a single OR at an academic institution from January 2020 to December 2020. Procedures from March 15, 2020, to May 4, 2020, were excluded to avoid COVID-related confounding. Temperature, humidity, and ABP count per minute were recorded with a particle counter intraoperatively and cross-referenced with surgical data from the electronic health records using procedure start and end times. Descriptive statistics were used to evaluate the differences in variables. P values were calculated using t-test and chi-square test. RESULTS: A total of 107 TKA cases were included: 79 (73.8%) primary TKAs and 28 (26.2%) rTKAs. Time spent in an OR was significantly higher for rTKAs (primary: 176 ± 46.7 minutes vs revision: 220 ± 47.1 minutes, P < .0001). Compared to primary TKAs, rTKAs had significant percent increases in ABP rates for particles measuring 0.3 µm (+70.4%, P < .001), 0.5 µm (+97.2%, P < .0001), 1.0 µm (+53.2%, P = .001), and 2.5 µm (+30.3%, P = .017) and for PM 2.5 (+108.3%, P < .001) and PM 5.0 (+105.6%, P < .001). CONCLUSION: rTKAs had significantly longer time spent in an OR and significant percent increases in ABP rates for particles measuring 0.3 µm, 0.5 µm, and 1.0 µm compared to primary TKAs. Measurements of PM 2.5 and 5.0 (which can contain large numbers of microbes) were also significantly greater in rTKAs. Further research is needed to determine whether the size and quantity of ABPs translate to higher infection rates after rTKA.

Impact of Preoperative Anemia Severity on Primary Total Hip Arthroplasty Outcomes.

BACKGROUND: Preoperative anemia (POA) is a significant predictor for adverse outcomes in primary total hip arthroplasty (THA). Current literature has studied POA stratified by severity. This study aims to find a threshold preoperative hemoglobin (Hb) value for increased risk of adverse outcomes in THA. METHODS: This is a retrospective analysis of primary THA patients with preoperative Hb values from 2014 to 2021 from an academic orthopedic specialty hospital. Demographics, surgical data, and postoperative outcomes were collected. Patients without preoperative Hb values within the electronic health record system or values acquired >30 days preoperatively were excluded. Patients were grouped based on POA severity using World Health Organization criteria. Secondary analysis using discrete preoperative Hb values was performed. P-values were calculated using analysis of variance/Kruskal-Wallis and chi-squared/Fisher's exact testing with P < .05 considered significant. RESULTS: A total of 1347 patients were included: 771 (57.2%) patients with POA and 576 (42.8%) with normal preoperative Hb. In the POA group, 292 (37.9%) were mild, 445 (57.7%) moderate, and 34 (4.4%) severe. Increased length of stay was seen in moderate (3.9 ± 4.3 vs 2.4 ± 2.1, P < .001) and severe (5.0 ± 3.4 vs 2.4 ± 2.1, P < .0001) groups compared to control. The severe group had higher 90-day readmission and revision rates compared to control. Analysis by discrete Hb values showed increased length of stay in Hb values <11 g/dL and a greater proportion of patients with Hb values <12 g/dL were discharged to skilled nursing facilities. CONCLUSION: Patients with preoperative Hb <12 g/dL should be assessed for other risk factors that may predispose them to postoperative complications. Further investigation is warranted to develop more robust perioperative management strategies for POA patients undergoing THA. LEVEL III EVIDENCE: Retrospective Cohort Study.

Postoperative venous thromboembolism event increases risk of readmissions and reoperation following total joint arthroplasty: a propensity-matched cohort study.

PURPOSE: The clinical impact of postoperative venous thromboembolism (VTE) following total joint arthroplasty (TJA) remains unclear. In this study, we evaluate the effect of VTE following TJA on postoperative outcomes including discharge disposition, readmission rates, and revision rates. METHODS: We retrospectively reviewed all patients over the age of 18 who underwent primary, elective THA or TKA between 2013 and 2020. Patients were stratified into two cohorts based on whether or not they had a VTE following their procedure. Baseline patient demographics and clinical outcomes such as readmissions and revisions were collected. Propensity score matching was performed to limit significant demographic differences, while independent sample t-tests and Pearson's chi-squared test were used to compare outcomes of interest between the groups. RESULTS: After propensity score matching, there were 109 patients in each cohort, representing a total of 218 patients for the matched comparison. Prior to matching, the VTE cohort was noted to have a significantly higher BMI than the non-VTE cohort (32.22 ± 6.27 vs 30.93 ± 32.04 kg/m2, p = 0.032). All other patient demographics were similar. Compared to the non-VTE cohort, the VTE cohort was less likely to be discharged home (66.1% vs 80.7%; p = 0.021), had a higher rate of 90-day all-cause readmissions (27.5% vs 9.2%, p = 0.001), and a higher two-year revision rate (11.0% vs 0.9%, p = 0.003). CONCLUSION: Patients with postoperative VTE were less likely to be discharged home and had higher 90-day readmission and two-year revision rates. Therefore, mitigating perioperative risk factors, initiating appropriate long-term anticoagulation, and maintaining close follow-up for patients with postoperative VTE may play significant roles in decreasing hospital costs and the economic burden to the healthcare system. LEVEL OF EVIDENCE III: Retrospective Cohort Study.

Are Patient-Reported Drug Allergies Associated With Prosthetic Joint Infections and Functional Outcomes Following Total Hip and Knee Arthroplasty?

BACKGROUND: The purpose of this study is to determine if the number and types of patient-reported drug allergies are associated with prosthetic joint infection (PJI) and functional outcomes following total joint arthroplasty (TJA). METHODS: This is a retrospective review of all patients who underwent a primary, elective total hip (THA) or knee arthroplasty (TKA) over a 10-year period at a single academic institution. Demographic, clinical information, and number and type of patient-reported drug allergy was collected. Univariate and multivariate logistic regressions were performed to identify risk factors for PJI and risk of PJI based on number of allergies. Univariate analysis was also performed to identify if the number of patient-reported allergies affected functional outcome scores. RESULTS: Of 31,109 patients analyzed, there were 941 (3%) revisions for infection (491 knees and 450 hips). At least one allergy was reported by 16,435 (52.8%) patients, with a mean of 1.2 ± 1.9. Those who underwent revision for infection had a significantly higher number of reported allergies (1.68 ± 1.9 vs 1.23 ± 1.9, P < .0005, 95% confidence interval -0.58 to 0.33). On univariate regression the number of allergies independently predicted revision TJA for infection (P < .0001) as did age, gender, body mass index, and smoking status. On multivariate regression for each additional patient-reported allergy, risk of PJI increased by 1.11 times (95% confidence interval 1.07-1.14, P < .0001). Number of patient-reported allergies did not predict 3-month or 1-year functional outcome scores. CONCLUSION: Patients with a higher number of reported allergies may be at increased risk of PJI following TJA. LEVEL OF EVIDENCE: Prognostic Level II.

The 2021 Centers for Medicare and Medicaid Services Fee Schedule's Impact on Adult Reconstruction Surgeon Productivity and Reimbursement.

BACKGROUND: On December 20, 2020, the Centers for Medicare and Medicaid Services (CMS) finalized its proposed rule: CMS-1734-P. This 2021 Final Rule significantly changed Medicare total joint arthroplasty (TJA) reimbursement. The precise impact on surgeon productivity and reimbursement is unknown. In the present study, we sought to model the potential impact of these changes for multiple unique practice configurations. METHODS: A mathematical model was applied to CMS data to determine the impact of CMS-1734-F on multiple, theoretical TJA practice configurations. Variables tested were the annual percentage of revision vs primary arthroplasty cases performed and the annual percentage of operative vs office-based productivity. The model defined baseline annual surgeon productivity as the 2018 Medical Group Management Association hip and knee arthroplasty surgeon median productivity of 10,568 work relative value units (wRVUs). RESULTS: All modeled simulations demonstrated a year-to-year increase in wRVUs independent of practice configuration. However, simulations that demonstrated less than a 3.35% increase in wRVUs from year-to-year saw a decrease in reimbursement. Those simulations with higher wRVU increases tended to have a higher percentage of revision vs primary arthroplasty cases and/or had annual productivity that was derived to a greater extent from office encounters than surgical cases. CONCLUSION: The impact of CMS-1734-F will vary based on 3 factors: (1) the relative contribution of a surgeon's operative TJA practice compared with their office-based practice to their annual wRVUs; (2) the relative percentage of revision TJAs vs the percentage of primary TJAs performed; and (3) the relative percentage of primary TJA compared to non-arthroplasty surgeries as a component of overall operative practice. The decreased reimbursement will be disproportionately felt by arthroplasty surgeons who perform relatively fewer revision TJA procedures and whose office-based productivity makes up a smaller overall percentage of their annual workload.

Femoral Head Osteonecrosis in Systemic Lupus Erythematosus: Total Hip Arthroplasty Outcomes and Considerations.

¼: Osteonecrosis of the femoral head disproportionately affects patients with systemic lupus erythematosus (SLE) and is the most frequent indication for total hip arthroplasty (THA) in these patients. ¼: Patients with SLE are more likely to undergo THA than those without the disease, and they elect for the procedure at a younger age. More arthroplasty procedures are currently being performed on patients with SLE as the all-cause rate of arthroplasty is increasing similarly to that of the general population. ¼: Postoperatively, patients with SLE report similar functional outcomes but lower physical quality of life compared with their peers. Sociodemographic factors should be considered as barriers to recovery and should be taken into account during patient counseling. ¼: Past research regarding the postoperative infection risk following THA in patients with SLE has been unclear. Recent high-power data indicate that these patients have a higher risk of periprosthetic infection for unclear reasons. ¼: SLE is an independent risk factor for perioperative medical complications, including the need for blood transfusion, genitourinary complications, sepsis, acute renal disease, deep venous thrombosis, and falls, among other adverse events. The current perioperative treatment guidelines were founded on low-to-moderate-quality studies.