Perioperative pain protocols following surgery for adolescent idiopathic scoliosis: a snapshot of current treatments utilized by attending orthopedic surgeons.

PURPOSE: Perioperative management after adolescent idiopathic scoliosis (AIS) surgery varies extensively between surgeons and institutions. We devised a questionnaire to assess surgeon baseline characteristics, practice settings, and pain regimens to assess what factors contribute to perioperative pain protocols. METHODS: A multiple-choice questionnaire including 130 independent variables regarding baseline characteristics, practice environments, and pain regimen protocols was distributed to elicit information among surgeons performing AIS fusion surgery. Pairwise bivariate analysis between practice location, length of practice, and practice environment vs. type of post-operative analgesia was completed using two-tailed Fisher's exact test. RESULTS: 85 respondents participated, all identified as practicing orthopedic surgeons. The largest group of respondents reported 20-40% of their total practice was dedicated to AIS (36%). Respondents were predominantly hospital-employed academic physicians (67%). The most common pain medication administered preoperatively was gabapentin (54%). Postoperative regimens were highly varied. Discharge pain regimens most commonly included short-acting opiates (89%), acetaminophen (86%), antispasmodics (59%), and NSAIDs (51%). Bivariate analysis revealed that fentanyl PCA was significantly associated with practice location (p < 0.05). Utilization of NSAIDs was significantly associated with length in training, with older physicians utilizing anti-inflammatories more regularly than younger physicians (p < 0.05). CONCLUSION: This study identifies common perioperative regimens utilized in AIS surgery. Of interest, younger surgeons are less likely to prescribe NSAIDs post-operatively than surgeons who have been in practice for longer periods of time, which may represent a bias against anti-inflammatory medications in younger surgeons.

Impact of Surgeon Case Volume on Outcomes After Reverse Total Shoulder Arthroplasty.

INTRODUCTION: Despite a rapid increase in utilization of reverse total shoulder arthroplasty (rTSA), volume-outcome studies focusing on surgeon volume are lacking. Surgeon-specific volume-outcome studies may inform policymakers and provide insight into learning curves and measures of efficiency with greater case volume. METHODS: This retrospective cohort study with longitudinal data included all rTSA cases as recorded in the Centers for Medicare & Medicaid Services Limited Data Set (2016 to 2018). The main effect was surgeon volume; this was categorized using two measures of surgeon volume: (1) rTSA case volume and (2) rTSA + TSA case volume. Volume cutoff values were calculated by applying a stratum-specific likelihood ratio analysis. RESULTS: Among 90,318 rTSA cases performed by 7,097 surgeons, we found a mean annual rTSA surgeon volume of 6 ± 10 and a mean rTSA + TSA volume of 9 ± 14. Regression models using surgeon-specific rTSA volume revealed that surgery from low (<29 cases) compared with medium (29 to 96 cases) rTSA-volume surgeons was associated with a significantly higher 90-day all-cause readmission (odds ratio [OR], 1.17; confidence interval [CI], 1.10 to 1.25; P < 0.0001), higher 90-day readmission rates because of an infection (OR, 1.46; CI, 1.16 to 1.83; P = 0.0013) or dislocation (OR, 1.43; CI, 1.19 to 1.72; P = 0.0001), increased 90-day postoperative cost (+11.3% CI, 4.2% to 19.0%; P = 0.0016), and a higher transfusion rate (OR, 2.06; CI, 1.70 to 2.50; P < 0.0001). Similar patterns existed when using categorizations based on rTSA + TSA case volume. CONCLUSION: Surgeon-specific volume-outcome relationships exist in this rTSA cohort, and we were able to identify thresholds that may identify low and medium/high volume surgeons. Observed volume-outcome relationships were independent of the definition of surgeon volume applied: either by focusing on the number of rTSAs performed per surgeon or anatomic TSAs performed. LEVEL OF EVIDENCE: III.

Factors Associated With Amputation Following Ankle Fracture Surgery.

Patients with diabetes mellitus (DM) are at increased risk of complications following ankle fracture surgery. Previous research suggests that patients of low socioeconomic status are at increased risk of amputation following orthopedic complications. The purpose of this research was to determine if low socioeconomic status increases risk of below-knee amputation (BKA) following ankle fractures among patients with DM. The National Inpatient Sample (NIS) was queried from 2010 to 2014 to identify 125 diabetic patients who underwent ankle fracture surgical fixation followed by BKA. Two cohorts (BKA vs no BKA) and a multivariate logistic regression model were created to compare the effects of independent variables, including age, sex, race, primary payer, median household income by ZIP code, hospital location/teaching status, and comorbidities. The most predictive variables for BKA were concomitant peripheral vascular disease (odds ratio [OR] 5.35, 95% confidence interval [CI] 3.51-8.15), history of chronic diabetes-related medical complications (OR 3.29, CI 2.16-5.01), age in the youngest quartile (OR 2.54, CI 1.38-4.67), and male sex (OR 2.28, CI 1.54-3.36). Patient race and median household income were not significantly associated with BKA; however, risk of BKA was greater among patients with Medicaid (OR 2.23, CI 1.09-4.53) or Medicare (OR 1.85, CI 1.03-3.32) compared to privately insured patients. Diabetic inpatients with Medicaid insurance are at over twice the odds of BKA compared to privately insured patients following ankle fracture. Furthermore, peripheral vascular diseases, uncontrolled diabetes, younger age, and male sex each independently increase risk of BKA.

Marijuana Use is Not a Contraindication for Tranexamic Acid Utilization in Lumbar Spine Surgery.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The purpose of this study was to evaluate safety in lumbar spinal fusion with tranexamic acid (TXA) utilization in patients using marijuana. METHODS: This was a retrospective cohort study involving a single surgeon's cases of 1 to 4 level lumbar fusion procedures. Two hundred and ninety-four patients were followed for ninety days post-operatively. Consecutive patients were self-reported for daily marijuana use (n = 146) and compared to a similar cohort of patients who denied usage of marijuana (n = 146). Outcomes were collected, which included length of stay (LOS), estimated blood loss (EBL), post-operative myocardial infarction, seizures, deep venous thrombosis, pulmonary embolus, death, readmission, need for further surgery, infection, anaphylaxis, acute renal injury, and need for blood product transfusion. RESULTS: Patients in the marijuana usage cohort had similar age (58.9 years ±12.9 vs 58.7 years ±14.8, P = .903) and distribution of levels fused (P = .431) compared to the non-usage cohort. Thromboembolic events were rare in both groups (marijuana usage: 1 vs non-usage: 2). Compared to the non-usage cohort, the marijuana usage cohort had a similar average EBL (329.9 ± 298.5 mL vs 374.5 ± 363.8 mL; P = .254). Multivariate regression modeling demonstrated that neither EBL (OR 1.27, 95% CI 0.64-2.49) nor need for transfusion (OR 1.56, 95% CI 0.43-5.72) varied between cohorts. The non-usage cohort had twice the risk of prolonged LOS compared to the marijuana usage cohort (OR 2.05, 95% CI 1.15-3.63). CONCLUSION: Marijuana use should not be considered a contraindication for TXA utilization in lumbar spine surgery.

Cannabis Use Does Not Increase Risk of Perioperative Complications Following Primary Total Hip Arthroplasty: A Cohort-Matched Comparison.

Introduction: Cannabis use among arthroplasty patients has dramatically increased throughout the United States. Despite this trend, knowledge remains particularly limited regarding the effects of cannabis use on perioperative outcomes in total hip arthroplasty (THA). Therefore, the goal of this research was to investigate how cannabis use affects risk of perioperative outcomes, cost and length of stay (LOS) after THA. Materials and Methods: The National Inpatient Sample was used to identify 331,825 patients who underwent primary THA between 2010 and 2014 using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9) procedure code 81.51. Patients with an ICD-9 diagnosis code correlating to history of thromboembolic events, cardiac events, or active substance use other than cannabis were eliminated. The ICD-9 diagnosis codes for cannabis use (304.3-304.32, 305.2-305.22) were used to identify 538 patients with active use. Cannabis users were matched 1:1 to nonusers on age, sex, tobacco use, and comorbidities. The chi-square test was used to determine risk of major and minor complications, whereas the Kruskal-Wallis H test was used to compare hospital charges and LOS. Results: A total of 534 (99.3%) patients with cannabis use were successfully matched with 534 patients without cannabis use. Risk of major complications among cannabis users (25, 4.68%) was similar to that of nonusers (20, 3.74%, p=0.446). Minor complications also occurred at similar rates between cannabis users (77, 14.4%) and nonusers (87, 16.3%, p=0.396). LOS for cannabis users (3.07±2.40) did not differ from nonusers (3.10±1.45, p=0.488). Mean hospital charges were higher for cannabis users ($17,847±10,024) compared with nonusers ($16,284±7025, p<0.001). Conclusion: Utilizing statistically matched cohorts within a nationally representative database demonstrated that cannabis use is not associated with increased risk of complications or prolonged LOS after primary THA. However, cannabis use is associated with higher hospital charges.

The Cost of Robot-assisted Total Hip Arthroplasty: Comparing Safety and Hospital Charges to Conventional Total Hip Arthroplasty.

INTRODUCTION: Utilization of robotic assistance is increasing for total hip arthroplasty (THA). However, few studies have directly examined the efficacy of this technique at reducing complications. This research aims to compare the rates of perioperative complications of robotic-assisted THA (RA-THA) with conventional THA (C-THA). METHODS: This study screened more than 35 million hospital discharges between 2010 to 2014 using the National Inpatient Sample. The International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) procedure codes were used to identify 292,836 patients who underwent C-THA (ICD 81.51) and 946 patients who underwent RA-THA (ICD 81.51 and ICD 17.41, 17.49). Perioperative complications were identified using ICD-9-CM diagnosis codes. Patient mortality was determined using the Uniform Bill patient disposition. The RA-THA cohort was statistically matched 1:1 to C-THA about patient age, sex, race, comorbidities, hospital type, and calendar year. Mean cost and length of stay (LOS) for each cohort were calculated and compared using the Kruskal-Wallis H test. Logistic regression was used to compare the risks of major and minor complications between the cohorts. RESULTS: We matched 758 (80.13%) RA-THA patients with 758 patients who underwent C-THA. No patient in our sample died. When compared with the conventional group, multivariate analysis revealed that the risk of major complications was similar in RA-THA patients (odds ratio = 0.698, 95% confidence interval = 0.282 to 1.727). In addition, although the rate of minor complications was higher in the RA-THA cohort (21.6% versus 12.5%, P = 0.004), no difference was observed on multivariate analysis (odds ratio = 1.248, 95% confidence interval = 0.852 to 1.829). The average inpatient hospital cost of a RA-THA was $20,046 (SD = 6,165) compared with $18,258 (SD = 6,147) for C-THA (P < 0.001). The average LOS was for RA-THA was 2.69 days (SD = 1.25) compared with 2.82 days for C-THA (SD = 1.18, P < 0.001). DISCUSSION: In a statistically matched cohort, the risk of perioperative complication in patients who underwent RA-THA versus C-THA patients were similar. However, RA-THA was costlier despite shorter LOS. LEVEL OF EVIDENCE: Level III, retrospective cohort analysis.

In-Hospital Complications following Arthrotomy versus Arthroscopy for Septic Knee Arthritis: A Cohort-Matched Comparison.

There is a paucity of literature comparing the relative merits of open arthrotomy versus arthroscopy for the surgical treatment of septic knee arthritis. The primary goal of this study is to compare the risk of perioperative complications between these two surgical techniques. To this end, 560 patients treated for septic arthritis of the native knee with arthroscopy were statistically matched 1:1 with 560 patients treated with open arthrotomy. The outcome measures included major complications, minor complications, mortality, inpatient hospital charges, and length of stay (LOS). Major complications were defined as myocardial infarction, cardiac arrest, stroke, deep vein thrombosis, pulmonary embolism, pneumonia, postoperative shock, unplanned ventilation, deep surgical site infection, wound dehiscence, infected postoperative seroma, hospital acquired urinary tract infection, and retained surgical item. Minor complications included phlebitis and thrombophlebitis, postprocedural emphysema, minor surgical site infection, peripheral nerve complication, and intraoperative hemorrhage. Mortality data were extracted from the database using the Uniform Bill patient disposition. Complications were analyzed using univariate and multivariate logistic regression models, whereas mean costs and LOS were compared using the Kruskal-Wallis H-test. Major complications occurred in 3.8% of the patients in the arthroscopy cohort and 5.4% of the patients in the arthrotomy cohort (p = 0.20). Too few patients in our sample died to report based on National (Nationwide) Impatient Sample (NIS) minimum reporting standards. Rates of minor complications were similar for the arthroscopy and arthrotomy cohorts (12.5 vs. 13.9%; p = 0.48). Multivariate analysis did not reveal any greater risk of minor or major complication between the two procedures. Inpatient hospital cost was similar for arthroscopy ( = $15,917; standard deviation [SD] = 14,424) and arthrotomy ( = $16,020; SD = 18,665; p = 0.42). LOS was also similar for both arthrotomy (6.78 days, SD = 6.75) and arthroscopy (6.24 days, SD = 5.95; p = 0.23). Patients undergoing arthroscopic treatment of septic arthritis of the knee showed no difference in relative risk of perioperative complications, LOS, or hospital cost compared with patients who underwent open arthrotomy.

The Cost-Effectiveness of Vancomycin Powder in Lumbar Laminectomy.

STUDY DESIGN: Break-even cost analysis. OBJECTIVE: The goal of this study is to examine the cost-effectiveness of vancomycin powder for preventing infection following lumbar laminectomy. METHODS: The product cost of vancomycin powder was obtained from our institution's purchasing records. Infection rates and revision costs for lumbar laminectomy and lumbar laminectomy with fusion were obtained from the literature. A break-even analysis was then performed to determine the absolute risk reduction (ARR) in infection rate to make prophylactic application of vancomycin powder cost-effective. Analysis of lumbar laminectomy with fusion was performed for comparison. RESULTS: Costing $3.06 per gram at our institution, vancomycin powder was determined to be cost-effective in lumbar laminectomy if the infection rate of 4.2% decreased by an ARR of 0.015%. Laminectomy with fusion was also determined to be cost-effective at the same cost of vancomycin powder if the infection rate of 8.5% decreased by an ARR of 0.0034%. The current highest cost reported in the literature, $44.00 per gram of vancomycin powder, remained cost-effective with ARRs of 0.21% and 0.048% for laminectomy and laminectomy with fusion, respectively. Varying the baseline infection rate did not influence the ARR for either procedure when the analysis was performed using the product cost of vancomycin at our institution. CONCLUSIONS: This break-even analysis demonstrates that prophylactic vancomycin powder can be highly cost-effective for lumbar laminectomy. At our institution, vancomycin powder is economically justified if it prevents at least one infection out of 6700 lumbar laminectomy surgeries.

Socioeconomic Status Is Associated With the Risk of Girdlestone Resection Arthroplasty After Periprosthetic Infection of the Hip.

INTRODUCTION: Girdlestone resection arthroplasty (GRA) is a radical but sometimes necessary treatment of periprosthetic joint infection (PJI) of the hip. The purpose of this of this study was to identify the independent risk factors for GRA after PJI of the hip. METHODS: This is a retrospective, cross-sectional analysis of the National (Nationwide) Inpatient Sample from 2010 to 2014. The International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) was used to identify 27,404 patients with PJI of the hip, including 889 patients who underwent GRA (ICD-9-CM 80.05). A multivariate model was created to examine the association between GRA and patient characteristics such as age, sex, race, primary payer, median household income, and location and teaching status of the hospital where the procedure was performed. Furthermore, the model controlled for patient comorbidities, including diabetes, anemias, hypertension, congestive heart failure, chronic pulmonary disease, peripheral vascular disease, and drug abuse. RESULTS: The strongest independent risk factor for GRA was Medicare insurance (odds ratio [OR], 1.859, 95% confidence interval [CI], 1.500 to 2.304). Medicaid insurance was also associated with GRA (OR, 1.662, CI, 1.243 to 2.223). Compared with the wealthiest quartile for household income, patients in the poorest quartile (OR, 1.299, CI, 1.046 to 1.614) and second poorest quartile (OR, 1.269, CI, 1.027 to 1.567) were significantly more likely to have a GRA. Furthermore, patients older than 80 years old were at a higher risk of GRA than all other age groups (P < 0.05). No statistical differences were seen regarding patient race or sex. CONCLUSIONS: This study demonstrates that poorer patients, patients with government health insurance plans, and elderly patients are each at independently heightened risk of undergoing a GRA for the treatment of PJI of the hip. LEVEL OF EVIDENCE: III, retrospective cohort study.

Low Socioeconomic Status Is Associated With Increased Complication Rates: Are Risk Adjustment Models Necessary in Cervical Spine Surgery?

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: The objective of this study was to determine whether lower socioeconomic status was associated with increased resource utilization following anterior discectomy and fusion (ACDF). METHODS: The National Inpatient Sample database was queried for patients who underwent a primary, 1- to 2-level ACDF between 2005 and 2014. Trauma, malignancy, infection, and revision surgery were excluded. The top and bottom income quartiles were compared. Demographics, medical comorbidities, length of stay, complications, and hospital cost were compared between patients of top and bottom income quartiles. RESULTS: A total of 69 844 cases were included. The bottom income quartile had a similar mean hospital stay (2.04 vs 1.77 days, P = .412), more complications (2.45% vs 1.77%, P < .001), and a higher mortality rate (0.18% vs 0.11%, P = .016). Multivariate analysis revealed bottom income quartile was an independent risk factor for complications (odds ratio = 1.135, confidence interval = 1.02-1.26). Interestingly, the bottom income quartile experienced lower mean hospital costs ($17 041 vs $17 958, P < .001). CONCLUSION: Patients in the lowest income group experienced more complications even after adjusting for comorbidities. Therefore, risk adjustment models, including socioeconomic status, may be necessary to avoid potential problems with access to orthopedic spine care for this patient population.

National trends in total hip arthroplasty for traumatic hip fractures: An analysis of a nationwide all-payer database.

BACKGROUND: Hemiarthroplasty (HA) has traditionally been the treatment of choice for elderly patients with displaced femoral neck fractures. Ideal treatment for younger, ambulatory patients is not as clear. Total hip arthroplasty (THA) has been increasingly utilized in this population however the factors associated with undergoing HA or THA have not been fully elucidated. AIM: To examine what patient characteristics are associated with undergoing THA or HA. To determine if outcomes differ between the groups. METHODS: We queried the Nationwide Inpatient Sample (NIS) for patients that underwent HA or THA for a femoral neck fracture between 2005 and 2014. The NIS comprises a large representative sample of inpatient hospitalizations in the United States. International Classifications of Disease, Ninth Edition (ICD-9) codes were used to identify patients in our sample. Demographic variables, hospital characteristics, payer status, medical comorbidities and mortality rates were compared between the two procedures. Multivariate logistic regression analysis was then performed to identify independent risk factors of treatment utilized. RESULTS: Of the total 502060 patients who were treated for femoral neck fracture, 51568 (10.3%) underwent THA and the incidence of THA rose from 8.3% to 13.7%. Private insurance accounted for a higher percentage of THA than hemiarthroplasty. THA increased most in urban teaching hospitals relative to urban non-teaching hospitals. Mean length of stay (LOS) was longer for HA. The mean charges were less for HA, however charges decreased steadily for both groups. HA had a higher mortality rate, however, after adjusting for age and comorbidities HA was not an independent risk factor for mortality. Interestingly, private insurance was an independent predictor for treatment with THA. CONLUSION: There has been an increase in the use of THA for the treatment of femoral neck fractures in the United States, most notably in urban hospitals. HA and THA are decreasing in total charges and LOS.

Cost-effectiveness of Preoperative Staphylococcus aureus Screening and Decolonization in Cochlear Implantation.

OBJECTIVE: Infection following cochlear implantation is medically and economically devastating. The cost-effectiveness (CE) of colonization screening and decolonization for infection prophylaxis in cochlear implantation has not been examined. STUDY DESIGN: An analytic observational study of data collected from purchasing records and the literature. METHODS: Costs of Staphylococcus aureus colonization screening and decolonization were acquired from purchasing records and the literature. Infection rates after cochlear implantation and average total costs for evaluation and treatment were obtained from a review of the literature. A break-even analysis was performed to determine the required absolute risk reduction (ARR) in infection rate to make colonization screening or decolonization CE. RESULTS: Nasal screening ($144.07) is CE if the initial infection rate (1.7%) had an ARR of 0.60%. Decolonization with 2% intranasal mupirocin ointment ($5.09) was CE (ARR, 0.02%). A combined decolonization technique (2% intranasal mupirocin ointment, chlorhexidine wipes, chlorhexidine shower, and prophylactic vancomycin: $37.57) was CE (ARR, 0.16%). Varying infection rate as high as 15% demonstrated that CE did not change by maintaining an ARR of 0.16%. CE of the most expensive decolonization protocol was enhanced as the cost of infection treatment increased, with an ARR of 0.03% at $125,000. CONCLUSIONS: Prophylactic S aureus decolonization techniques can be CE for preventing infection following cochlear implantation. Decolonization with mupirocin is economically justified if it prevents at least 1 infection out of 5000 implants. S aureus colonization screening needed high reductions in infection rate to be CE.

Are Patients Who Undergo THA for Infection at Higher Risk for 30-day Complications?

BACKGROUND: Value-based payment models, such as bundled payments, continue to become more widely adopted for total joint arthroplasty. However, concerns exist regarding the lack of risk adjustment in these payment and quality reporting models for THA. Providers who care for patients with more complicated problems may be financially incentivized to screen out such patients if reimbursement models fail to account for increased time and resources needed to care for these more complex patients. QUESTIONS/PURPOSES: (1) Are patients who undergo revision THA for infectious causes at greater adjusted risk of 30-day short-term major complications, return to the operating room, readmission, and mortality compared with patients undergoing aseptic revision? (2) What are other independent factors associated with the risk of 30-day major complications, readmission, and mortality in this patient population? METHODS: We queried the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database for all patients undergoing revision THA from 2012 to 2015. The NSQIP database allows for the analysis of 30-day surgical outcomes, including postoperative complications, return to the operating room, readmission, and mortality of patients from approximately 400 participating institutions. The NSQIP was selected over other larger databases, such as the National Impatient Sample (NIS), because the NSQIP includes readmission data and 30-day complications rates that were relevant to our study. Patients undergoing aseptic revision THA and those undergoing revision THA with a diagnosis of periprosthetic joint infection were identified. We identified 8973 patients who underwent revision THA and excluded six patients due to a diagnosis of malignancy leaving 8967 patients; 726 (8%) of these were due to infection. Demographic variables, medical comorbidities, and 30-day major complications, hospital readmissions, reoperations, and mortality were compared among patients undergoing aseptic and infected revision THA. A major complication was defined as myocardial infarction, postoperative mortality, sepsis, septic shock, and stroke. A multivariate logistic regression analysis was then performed to identify factors independently associated with the primary outcome of 30-day hospital readmission, and secondary endpoints of 30-day major complications, return to operating room, and mortality. RESULTS: Controlling for medical comorbidities and demographic factors, the patients who underwent THA for infection were more likely to experience a major complication (odds ratio [OR], 4.637; 95% confidence interval [CI], 2.850-7.544; p < 0.001) within 30 days of surgery and more likely to return to the operating room (OR = 1.548; 95% CI, 1.062-2.255; p = 0.023). However, there were no greater odds of 30-day readmission (OR, 1.354; 95% CI, 0.975-1.880; p = 0.070) or 30-day mortality (OR, 0.661; 95% CI, 0.218-2.003; p = 0.465). Preoperative malnutrition was associated with an increased risk of return to the operating room (OR, 1.561; 95% CI, 1.152-2.115; p = 0.004), 30-day readmission (OR, 1.695; 95% CI, 1.314-2.186; p < 0.001), and 30-day mortality (OR, 7.240; 95% CI, 2.936-17.851; p < 0.001). CONCLUSIONS: Patients undergoing revision THA for infection undergo reoperation and experience major complications more frequently in a 30-day episode of care than patients undergoing aseptic revision THA. Without risk adjustment to existing alternative payment and quality reporting models, providers may experience a disincentive to care for patients with infected THAs, who may face difficulties with access to care. LEVEL OF EVIDENCE: Level III, therapeutic study.

Socioeconomic Status Is Associated with Risk of Above-knee Amputation After Periprosthetic Joint Infection of the Knee.

BACKGROUND: Above-knee amputation (AKA) is a severe but rare complication of TKA. Recent evidence suggests there are sex and racial disparities with regard to AKA after TKA. However, whether lower socioeconomic status is associated with an increased risk of AKA after TKA has not been conclusively established. QUESTIONS/PURPOSES: (1) Is low socioeconomic status or use of public health insurance plans associated with an increased risk of AKA after periprosthetic joint infection (PJI) of the knee? (2) Is race or sex associated with an increased risk of AKA after PJI of the knee? METHODS: This cross-sectional study screened the National Inpatient Sample (NIS) between 2010 and 2014 using the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) procedure and diagnosis codes to identify 912 AKAs (ICD 84.17) among 32,907 PJIs of the knee. The NIS is a large national database of inpatient hospitalizations frequently used by researchers to study outcomes and trends in orthopaedic procedures. The NIS was selected over other databases with more complete followup data such as the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) due to its unique ability to examine income levels and insurance type. Cases were identified by taking all patients with an ICD diagnosis code related to PJI of the knee and limiting that cohort to patients with an ICD procedure code specific to TKA. A total of 912 AKAs after PJI were identified (912 of 32,907, [3%] of all PJIs of the knee) with males comprising 52% of the AKA sample (p = 0.196). Multivariate logistic regression was used to compare risk of AKA after PJI of the knee after controlling for patient demographics, hospital characteristics, and comorbidities. RESULTS: Compared with the wealthiest income quartile by ZIP code, patients in the lowest income quartile by ZIP code were more likely to sustain an AKA (OR = 1.58; 95% confidence interval [CI] 1.25-1.98; p < 0.001). Compared with patients with private insurance, patients with Medicare (OR = 1.94; 95% CI, 1.55-2.43; p < 0.001) and Medicaid (OR = 1.86; 95% CI, 1.37-2.53; p < 0.001) were at higher risk of AKA. There were no differences with regard to risk of AKA for white patients (670 of 24,004 [3%]; OR = 0.99; 95% CI, 0.77-1.26; p = 0.936) and black patients (95 of 3178 [3%], OR = 0.95; 95% CI, 0.69-1.30; p = 0.751) when compared with others (reference, 83 of 3159 [3%]). When compared with female patients, male patients did not have a greater risk of undergoing AKA (OR = 1.02; 95% CI, 0.88-1.29; p = 0.818). CONCLUSIONS: This study did not observe any racial or sex disparities with regard to risk of AKA after PJI. However, there was a greater risk of AKA after PJI for poorer patients and patients participating in Medicare or Medicaid insurance plans. Surgeons should be cognizant when treating PJI in patients from lower income backgrounds as these patients may be at greater risk for AKA. Future research should explore the role of physician attitudes or preconceptions about predicted patient followup in treating PJI, as well as the effect of concurrent peripheral vascular disease on the risk of AKA after PJI. LEVEL OF EVIDENCE: Level III, therapeutic study.

Industry Consulting Payments to Orthopedic Surgeons Are Associated With Increased Publications.

In accordance with the Physician Payment Sunshine Act, all industry payments to physicians in the United States have become publicly available. Previous research has indicated that orthopedic surgeons receive the greatest amount of industry compensation compared with other surgical subspecialists. However, the relationship between this compensation and research productivity is less clear. This study sought to investigate the relationship between consulting fees paid to orthopedic surgeons and academic productivity. Using the Centers for Medicare & Medicaid Services Open Payments Database, this study identified 2555 orthopedic surgeons who received at least one industry consulting fee in 2015. Physicians who received total consulting fees of at least $20,000 (US) were stratified into the high payment group. The number of publications and the h-index for each physician were used as metrics of scholarly impact. Mean publication number and h-index for the high payment group were compared with all other physicians in the sample using an independent-samples t test. A total of 2555 orthopedic surgeons received consulting payments totaling $62,323,143 in 2015. The mean consulting payment was $24,393 (SD, $45,465). The publication number was greater for the high payment group (mean, 61.6; SD, 135.6) compared with all other physicians in the sample (mean, 36.1; SD, 95.6). Additionally, the mean h-index for the high payment group was 13.7 (SD, 14.3) compared with 10.0 (SD, 11.6) for all other orthopedic surgeons. These findings indicate that the orthopedic surgeons who receive more in industry consulting fees are also those who contribute most substantially to the body of orthopedic literature. [Orthopedics. 2019; 42(3):137-142.].

The Cost Effectiveness of Dilute Betadine Lavage for Infection Prophylaxis in Total Joint Arthroplasty.

BACKGROUND: This article presents a break-even analysis for intraoperative Betadine lavage for the prevention of infection in total hip arthroplasty (THA) and total knee arthroplasty (TKA). METHODS: Protocol costs, baseline infection rates after arthroplasty, and average revision costs were obtained from institutional records and the literature. The break-even analysis determined the absolute risk reduction (ARR) in infection rate required for cost effectiveness. RESULTS: At our institutional price of $2.54, dilute (0.35%) Betadine lavage would be cost effective if initial infection rates of both TKA (1.10%) and THA (1.63%) have an ARR of 0.01%. At a hypothetical lowest cost of $0.50, the ARR is so low as to be immediately cost effective. At a hypothetical high price of $40.00, Betadine is cost effective with ARRs of 0.16% (TKA) and 0.13% (THA). CONCLUSION: Intraoperative Betadine lavage, at typical institutional prices, can be highly cost effective in reducing infection after joint arthroplasty.

Robotic-assisted pedicle screw placement fails to reduce overall postoperative complications in fusion surgery.

BACKGROUND CONTEXT: Surgeons have increasingly adopted robotic-assisted lumbar spinal fusion due to indications that robotic-assisted surgery can reduce pedicle screw misplacement. However, the impact of robotic-assisted spinal fusion on patient outcomes is less clear. PURPOSE: This study aimed to compare rates of perioperative complications between robotic-assisted and conventional lumbar spinal fusion. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: A total of 520 patients undergoing lumbar fusion were analyzed. The average ages of patients in the robotic-assisted versus conventional groups were 60.33 and 60.31, respectively (p=.987). Patients with a diagnosis of fracture, traumatic spinal cord injury, spina bifida, neoplasia, or infection were excluded. OUTCOME MEASURES: This study compared the rates perioperative major and minor complications for elective lumbar fusion between each cohort. METHODS: This study screened hospital discharges in the United States from 2010 to 2014 using the National Inpatient Sample and the Nationwide Inpatient Sample (NIS). The International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) procedure codes were used to identify 209,073 patients who underwent conventional lumbar fusion (ICD 81.04-8) and 279 patients who underwent robotic-assisted lumbar fusion (ICD 81.04-8 and ICD 17.41, 17.49). Major and minor complications were identified using ICD-9-CM diagnosis codes. The robotic-assisted and conventional fusion groups were statistically matched on age, year, sex, indication, race, hospital type, and comorbidities. Univariate and multivariate logistic regression were used to compare risks of major and minor complications. RESULTS: We matched 257 (92.11%) robotic-assisted patients with an equal number of patients undergoing conventional lumbar fusion. Minor complications occurred in 16.73% of cases in the conventional group and 31.91% of cases in the robotic-assisted group (p<.001). Major complications occurred in 6.61% of the conventional cases compared to 8.17% of robotic-assisted cases (p=.533). For robotic-assisted fusion, multivariate analysis revealed that there was no difference in the likelihood of major complications (OR=0.834, 95% CI=0.214-3.251) or minor complications (OR = 1.450, 95% CI=0.653-3.220). CONCLUSIONS: In a statistically matched cohort, patients who underwent robotic-assisted lumbar fusion had similar rates of major and minor complications compared to patients who underwent conventional lumbar fusion.

Antibody-modified conduits for highly selective cytokine elimination from blood.

Cytokines play an important role in dysregulated immune responses to infection, pancreatitis, ischemia/reperfusion injury, burns, hemorrhage, cardiopulmonary bypass, trauma, and many other diseases. Moreover, the imbalance between inflammatory and antiinflammatory cytokines can have deleterious effects. Here, we demonstrated highly selective blood-filtering devices - antibody-modified conduits (AMCs) - that selectively eliminate multiple specific deleterious cytokines in vitro. AMCs functionalized with antibodies against human vascular endothelial growth factor A or tumor necrosis factor α (TNF-α) selectively eliminated the target cytokines from human blood in vitro and maintained them in reduced states even in the face of ongoing infusion at supraphysiologic rates. We characterized the variables that determine AMC performance, using anti-human TNF-α AMCs to eliminate recombinant human TNF-α. Finally, we demonstrated selective cytokine elimination in vivo by filtering interleukin 1 ß from rats with lipopolysaccharide-induced hypercytokinemia.