Gloves Contamination During Revision Surgery for Periprosthetic Joint Infection.

BACKGROUND: The use of double gloving has become a standard practice for joint replacement surgeons. However, since there are limited data on how gloves are contaminated during both primary and revision arthroplasty, no precise protocol exists to direct surgeons on when, or if, to change their gloves. The goals of this preliminary study were to evaluate the contamination of gloves during total joint arthroplasties (TJAs). METHODS: We included 25 infected cases and 10 primaries, which were performed at the same institution using the same surgical protocol from 3 fellowship trained surgeons. Samples were taken every 20 minutes from the start of the surgery until the joint was irrigated. Procedural steps were noted. To evaluate cross-contamination during infected cases, we sampled gloves using blood agar plates. In primary cases, culture swabs of anterior chamfer cuts and sterile instruments on the back table were used as negative controls. Next-generation sequencing (NGS) was used as an adjunct to identify low virulence bacteria. RESULTS: In the primary cases, all samples were found culture negative but 3 (8.1%) of the 37 samples were found to have a low, unidentifiable bacterial mass via NGS testing. In the infected cases, 41 (59.4%) of the 69 samples yielded positive microbial results. The positivity rate was higher in the samples collected after the arthrotomy was performed (70%) compared to samples collected before the arthrotomy was performed (40%), and the surgeon was only dissecting superficial layers (P = .502). CONCLUSION: Gloves seem to be a common source of cross-contamination in the intraoperative field during revision TJA. Due to the higher percent of positive samples following the opening of the joint, we hypothesize that the arthrotomy allows for the spread of bacteria across the operative site. While further investigation is necessary to formulate a precise protocol for the changing of gloves during TJA, it may be beneficial to perform a thorough irrigation of the joint and change of the gloves immediately following arthrotomy.

Prior Authorization Leads to Administrative Burden and Delays in Treatment in Primary Total Joint Arthroplasty Patients.

BACKGROUND: The prior authorization (PA) process is often criticized by physicians due to increased administrative burden and unnecessary delays in treatment. The effects of PA policies on total hip arthroplasty (THA) and total knee arthroplasty (TKA) have not been well described. The purpose of this study was to analyze the use of PA in a high-volume orthopaedic practice across 4 states. METHODS: We prospectively collected data on 28,725 primary THAs and TKAs performed at our institution between 2020 and 2023. Data collected included patient demographics, payer approval or denial, time to approval or denial, the number of initial denials, the number of peer-to-peer (P2P) or addenda, and the reasons for denial. RESULTS: Seven thousand five hundred twenty eight (56.4%) patients undergoing THA and 8,283 (54%) patients undergoing TKA required PA, with a mean time to approval of 26.3 ± 34.6 and 33.7 ± 41.5 days, respectively. Addenda were requested in 608 of 7,528 (4.6%) THA patients and 737 of 8,283 (8.9%) TKA patients. From a total of 312 (4.1%) THA patients who had an initial denial, a P2P was requested for 50 (0.7%) patients, and only 27 (0.4%) were upheld after the PA process. From a total of 509 (6.1%) TKA patients who had an initial denial, a P2P was requested for 55 (0.7%) patients, and only 26 (0.3%) were upheld after the PA process. The mean time to denial in the THA group was 64.7 ± 83.5, and the most common reasons for denial were poor clinical documentation (25.9%) and lack of coverage (25.9%). The mean time to denial in the TKA group was 63.4 ± 103.9 days, and the most common reason for denial was not specified by the payer (46.1%). CONCLUSIONS: The use of PA to approve elective THA and TKA led to increased surgical waiting times and a high administrative burden for surgeons and healthcare staff.

Outcomes of Metaphyseal Cones and Stem Fixation Following Rotating Hinge in Complex Primary and Revision Total Knee Arthroplasty.

BACKGROUND: Although hinged prostheses have been used successfully in complex revision total knee arthroplasty (TKA), concerns exist regarding early failure due to aseptic loosening and other mechanical complications. The use of metaphyseal cones and hybrid cement fixation have been studied in unlinked constrained primary or revision TKA, but their impact on the survivorship of hinged prostheses has yet to be investigated. METHODS: We identified a consecutive series of 164 hinged prostheses and collected data on demographics, indications, complications, and re-revisions in patients who had fully cemented versus hybrid stems, with and without metaphyseal cones. A multivariate analysis was performed to identify independent variables associated with re-revision as the primary end point. RESULTS: In total, 84 patients (51.2%) had fully cemented stems, and 80 patients (48.8%) had hybrid stems. Cones were used in 73 patients (44.5%). At a mean follow-up of 3.4 ± 2.2 years, 42 patients underwent re-revision (25.8%), most commonly for infection (12.2%), followed by loosening (6.7%) and periprosthetic fracture (3.7%). Patients who had fully cemented stems had lower re-revision rates than hybrid fixation constructs (19 versus 26%, P = .043). Using multivariable regression, a construct with hybrid fixation with cones (odds ratio = 2.39; P = .037) was an independent risk factor for failure. Utilization of cones alone did not have an effect on re-revision rates at 3.4-year follow-up. CONCLUSIONS: While we found no difference with the use of cones, patients undergoing revision TKA with a hinge prosthesis and fully cemented stems had better overall survivorship than hybrid stems.

Fix or Replace? Comparable Outcomes with Internal Fixation and Distal Femoral Replacement for Periprosthetic Fractures above Total Knee Arthroplasty.

INTRODUCTION: The optimal treatment for periprosthetic fracture (PPfx) around total knee arthroplasty (TKA) remains a topic of debate. Due to its low incidence, comparative studies analyzing arthroplasty and fixation are lacking in the literature. The purpose of this study was to compare the outcomes of distal femoral replacement (DFR) and open reduction and internal fixation (ORIF) for distal femur PPfx. METHODS: We reviewed a consecutive series of 99 patients who underwent DFR (n = 54) or ORIF (n = 45) for distal femur PPfx. The indications for DFR were reviewed. Fractures were classified based on their relation to the implant using the Su classification. The primary outcome was re-revision, while secondary endpoints included inpatient complications, mortality within the first year, and mechanical complications such as loosening and non-union. RESULTS: Type 2 fractures were the most prevalent type in both groups (DFR 37 versus ORIF 48.9%), while Type 1 fractures were more commonly treated with ORIF (35.6 versus 16.7%) and Type 3 with DFR (46.3 versus 15.6%) (P = 0.003). The preferred techniques in the ORIF group were plate osteosynthesis (66.7%) and retrograde nailing (31.1%). At a mean follow-up of 4.2 years (range, 1 to 14.1), DFR and ORIF did not demonstrate any difference in revision rates (13 versus 24.4%, P = 0.140) or mortality (3.7 versus 4.4%, P = 0.887). However, more mechanical complications were noted in the ORIF group (22.2 versus 7.4%, P = 0.035). CONCLUSION: Both distal femoral replacement and open reduction and internal fixation have comparable revision rates, complications, and clinical outcomes when used in supracondylar periprosthetic distal femur fractures. Longer-term studies are needed to assess DFR survivorship as well as outcomes of newer trauma techniques such as nail-plate combinations.

Study protocol for a randomised placebo-controlled trial of pramipexole in addition to mood stabilisers for patients with treatment resistant bipolar depression (the PAX-BD study).

BACKGROUND: Treatment Resistant Bipolar Depression (TRBD) is a major contributor to the burden of disease associated with Bipolar Disorder (BD). Treatment options for people experiencing bipolar depression are limited to three interventions listed by National Institute for Health and Care: lamotrigine, quetiapine and olanzapine, of which the latter two are often not well tolerated. The majority of depressed people with BD are therefore prescribed antidepressants despite limited efficacy. This demonstrates an unmet need for additional interventions. Pramipexole has been shown to improve mood symptoms in animal models of depression, in people with Parkinson's Disease and two proof of principle trials of pramipexole for people with BD who are currently depressed. METHODS: The PAX-BD study, funded by the United Kingdom (UK) National Institute for Health Research, aims to extend previous findings by assessing the efficacy, safety and health economic impact of pramipexole in addition to mood stabilisers for patients with TRBD. A randomised, double-blind, placebo controlled design is conducted in a naturalistic UK National Health Service setting. An internal pilot study to examine feasibility and acceptability of the study design is included. Participants with TRBD are screened from National Health Service secondary care services in up to 40 mental health trusts in the UK, with the aim of recruiting approximately 414 participants into a pre-randomisation phase to achieve a target of 290 randomised participants. Primary safety and efficacy measures are at 12 weeks following randomisation, with follow up of participants to 52 weeks. The primary outcome is depressive symptoms as measured by Quick Inventory for Depressive Symptomatology - Self Report. Secondary outcomes include changes in anxiety, manic symptoms, tolerability, acceptability, quality of life and cost-effectiveness. Outcome measures are collected remotely using self-report tools implemented online, and observer-rated assessments conducted via telephone. ANCOVA will be used to examine the difference in rating scale scores between treatment arms, and dependent on compliance in completion of weekly self-report measures. A mixed effects linear regression model may also be used to account for repeated measures. TRIAL REGISTRATION: ISRCTN72151939. Registered on 28 August 2019, http://www.isrctn.com/ISRCTN72151939 Protocol Version: 04-FEB-2021, Version 9.0.

Risk Adjustment Is Necessary in Value-Based Payment Models for Arthroplasty for Oncology Patients.

BACKGROUND: Value-based payment models such as bundled payments have been introduced to reduce costs following total hip arthroplasty (THA). Concerns exist, however, about access to care for patients who utilize more resources. The purpose of this study is thus to compare resource utilization and outcomes of patients undergoing THA for malignancy with those undergoing THA for fracture or osteoarthritis. METHODS: We queried the American College of Surgeons National Surgical Quality Improvement Program database to identify all hip arthroplasties performed from 2013 to 2016 for a primary diagnosis of malignancy (n = 296), osteoarthritis (n = 96,480), and fracture (n = 13,406). The rates of readmissions, reoperations, comorbidities, mortality, and surgical characteristics were compared between the 3 cohorts. To control for confounding variables, a multivariate analysis was performed to identify independent risk factors for resource utilization and outcomes following THA. RESULTS: Patients undergoing THA for malignancy had a longer mean operative time (155.7 vs 82.9 vs 91.0 minutes, P < .001), longer length of stay (9.0 vs 7.2 vs 2.6 days, P < .001), and were more likely to be discharged to a rehabilitation facility (42.1% vs 61.8% vs 20.2%, P < .001) than patients with fracture or osteoarthritis. When controlling for demographics and comorbidities, patients undergoing THA for malignancy had a higher rate of readmission (adjusted odds ratio 3.39, P < .001) and reoperation (adjusted odds ratio 3.71, P < .001). CONCLUSION: Patients undergoing THA for malignancy utilize more resources in an episode-of-care and have worse outcomes. Risk adjustment is necessary for oncology patients in order to prevent access to care problems for these high-risk patients.

Complications and Mortality Following Total Hip Arthroplasty in the Octogenarians: An Analysis of a National Database.

BACKGROUND: As advances in medicine have increased life expectancy, more octogenarians are undergoing total hip arthroplasty (THA) than ever before. Concerns exist, however, about the safety of performing this elective procedure in this age group. The purpose of this study is to determine the 30-day complications associated with THA patients over 80 years of age and to identify high-risk patients. METHODS: We queried the American College of Surgeons-National Surgical Quality Improvement Program database for all patients who underwent primary THA from 2011 to 2014. Demographic variables, medical comorbidities, and 30-day complication, readmission, and reoperation rates were compared between patients under vs over 80 years of age. A multivariate logistic regression analysis was then performed to identify independent risk factors of poor short-term outcomes. RESULTS: Of the total 66,839 patients who underwent THA, 7198 (11%) patients were 80 years of age or older. Octogenarians had a higher overall complication rate (29% vs 15%, P < .001) and a higher mortality rate (0.9% vs 0.1%, P < .001). When controlling for other comorbidities, age over 80 years is an independent risk factor for mortality (odds ratio 2.02, 95% confidence interval 1.25-3.26, P = .004) and complications (odds ratio 1.41, 95% confidence interval 1.30-1.525, P < .001) following THA. Malnutrition and chronic kidney disease are also independent risk factors for readmission, complications, and mortality (all P < .05). CONCLUSION: THA in patients older than 80 years old are at an increased risk of complications and mortality. Octogenarian patients should be counseled on their risk profile, particularly those with malnutrition and chronic kidney disease.

How Many Cultures Are Necessary to Identify Pathogens in the Management of Total Hip and Knee Arthroplasty Infections?

BACKGROUND: Identification of the infecting organism is critical to the successful management of deep prosthetic joint infections about the hip and the knee. However, the number of culture specimens and which culture specimens are best to identify these organisms is unknown. METHODS: We evaluated 113 consecutive patients with infected total hip and total knee arthroplasties and correlated the type of culture specimen and number of specimens taken during surgery to the likelihood of a positive culture result. From these data, we subsequently developed a model to maximize culture yield at the time of surgical intervention. After exclusions, 74 patients meeting the Musculoskeletal Infection Society criteria were left for final analysis. RESULTS: From this cohort, 63 of 74 patients had a positive culture result (85%). The odds of a fluid culture result being positive was 35 of 47 (0.75), whereas the likelihood of tissue cultures yielding a positive result was 164 of 245 (0.67; P = .313). The sample designated "best culture" specimen was the only culture with a positive result in 1 of 48 cases in which a best culture was identified. The optimal number of cultures needed to yield a positive test result was 4 (specificity = 0.61 and sensitivity = 0.63). Increasing the number of samples increases sensitivity but reduces specificity. CONCLUSION: A minimum of 4 tissue cultures from representative areas is necessary to maximize the chance of identifying the infecting organism during management of the infected total hip and total knee arthroplasties. The designation of the best culture specimen for additional testing is arbitrary and may not be clinically efficacious.

Diagnosing Infection in Patients Undergoing Conversion of Prior Internal Fixation to Total Hip Arthroplasty.

BACKGROUND: Criteria for diagnosis of infected internal fixation implants at the time of conversion to total hip arthroplasty (THA) are not clear. The purpose of this study is to identify risk factors for infection in patients undergoing conversion to THA. METHODS: We retrospectively reviewed patients at a single institution who underwent conversion to THA from 2009 to 2014. Patients were diagnosed with infection preoperatively using Musculoskeletal Infection Society criteria or postoperatively if they were found to have positive cultures intraoperatively at the time of conversion surgery. Medical comorbidities and preoperative inflammatory markers were compared between infected and noninfected groups. Univariate and multivariate logistic regression analysis were performed to identify independent risk factors for infection. Receiver operating characteristic curves were generated to determine test performance of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). A post hoc power analysis was performed. RESULTS: Thirty-three patients were included in the study. Six patients (18%) were diagnosed with infection. We found no association between comorbidities and infection in this cohort. The mean ESR and CRP were higher in infected (ESR = 41.6 mm/h, CRP = 2.0 mg/dL) vs noninfected (ESR = 19.3 mm/h, CRP = 1.3 mg/dL) groups (both P < .01). ESR >30 mm/h (odds ratio 28.8, 95% confidence interval 2.6-315.4, P = .001) and CRP >1.0 mg/dL (odds ratio 11.5, 95% confidence interval 1.6-85.2, P = .01) were strongly associated with infection. Receiver operating characteristic curves for ESR (area under the curve [AUC] = 0.89) and CRP (AUC = 0.89) demonstrated good fit. CONCLUSION: We report a high incidence of infection in patients who underwent conversion to THA. Preoperative ESR and CRP are effective screening tools though occult infections may still be missed. Patients with borderline or elevated inflammatory markers should raise strong suspicion for infection.

Preoperative Opiate Use Independently Predicts Narcotic Consumption and Complications After Total Joint Arthroplasty.

BACKGROUND: Multimodal pain protocols have reduced opioid requirements and decreased complications after elective total hip arthroplasty (THA) and total knee arthroplasty (TKA). However, these protocols are not universally effective. The purposes of this study are to determine the risk factors associated with increased opioid requirements and the impact of preoperative narcotic use on the length of stay and inhospital complications after THA or TKA. METHODS: We prospectively evaluated a consecutive series of 802 patients undergoing elective primary THA and TKA over a 9-month period. All patients were managed using a multimodal pain protocol. Data on medical comorbidities and history of preoperative narcotic use were collected and correlated with deviations from the protocol. RESULTS: Of the 802 patients, 266 (33%) required intravenous narcotic rescue. Patients aged <75 years (odds ratio [OR], 1.85; 95% confidence interval [CI], 1.10-3.12; P = .019) and with preoperative narcotic use (OR, 2.74; 95% CI, 2.01-3.75; P < .001) were more likely to require rescue. Multivariate logistic regression analysis demonstrated that preoperative narcotic use (OR, 2.74; 95% CI, 2.01-3.75; P < .001) was the largest independent predictor of increased postoperative opioid requirements. These patients developed more inhospital complications (OR, 1.92; 95% CI, 1.34-2.76; P < .001). This was associated with an increased length of stay (OR, 1.59; 95% CI, 1.06-2.37; P = .025) and a 2.5-times risk of requiring oral narcotics at 3 months postoperatively (OR, 2.48; 95% CI, 1.61-3.82; P < .001). CONCLUSION: Despite the effectiveness of multimodal postoperative pain protocols, younger patients with preoperative history of narcotic use require additional opioids and are at a higher risk for complications and a greater length of stay.

Can Demographic Variables Accurately Predict Component Sizing in Primary Total Knee Arthroplasty?

BACKGROUND: As health care reform drives providers to reduce costs and improve efficiencies without compromising patient care, preoperative planning has become imperative. The purpose of this study is to determine whether height, weight, and gender can accurately predict total knee arthroplasty (TKA) sizing. METHODS: A consecutive series of 3491 primary TKAs performed by 2 surgeons was reviewed. Height, weight, gender, implant, preoperative templating sizes, and final implant sizes were collected. Implant-specific dimensions were collected from vendors. Using height, weight, and gender, a multivariate linear regression was performed with and without the inclusion of preoperative templating. Accuracy of the model was reported for commonly used implants. RESULTS: There was a significant linear correlation between height, weight, and gender for femoral (R2 = 0.504; P < .001) and tibial sizes (R2 = 0.610; P < .001). Adding preoperative templating to the regression analysis increased the overall model fit for both the femoral (R2 = 0.756; P < .001) and tibial sizes (R2 = 0.780; P < .001). Femoral and tibial sizes were accurately predicted within 1 size of the final implant 71%-92% and 81%-97% using demographics alone or 85%-99% and 90%-99% using both templating and demographics, respectively. CONCLUSION: This novel TKA templating model allows final implants to be predicted to within 1 size. The model allows for simplified preoperative planning and potential implementation into a cost-savings program that limits inventory and trays required for each case.

Are the Affordable Care Act Restrictions Warranted? A Contemporary Statewide Analysis of Physician-Owned Hospitals.

BACKGROUND: The Affordable Care Act placed a moratorium on physician-owned hospital (POH) expansion. Concern exists that POHs increase costs and target healthier patients. However, limited historical data support these claims and are not weighed against contemporary measures of quality and patient satisfaction. The purpose of this study was to investigate the quality, costs, and efficiency across hospital types. METHODS: One hundred forty-five hospitals in a single state were analyzed: 8 POHs; 16 proprietary hospitals (PHs); and 121 general, full-service acute care hospitals (ACHs). Multiyear data from the Centers for Medicare and Medicaid Services Medicare Cost Report and the statewide Health Care Cost Containment Council were analyzed. RESULTS: ACHs had a higher percentage of Medicare patients as a share of net patient revenue, with similar Medicare volume. POHs garnered significantly higher patient satisfaction: mean Hospital Consumer Assessment of Healthcare Providers and Systems summary rating was 4.86 (vs PHs: 2.88, ACHs: 3.10; P = .002). POHs had higher average total episode spending ($22,799 vs PHs: $18,284, ACHs: $18,856), with only $1435 of total spending on post-acute care (vs PHs: $3867, ACHs: $3378). Medicare spending per beneficiary and Medicare spending per beneficiary performance rates were similar across all hospital types, as were complication and readmission rates related to hip or knee surgery. CONCLUSION: POHs had better patient satisfaction, with higher total costs compared to PHs and ACHs. A focus on efficiency, patient satisfaction, and ratio of inpatient-to-post-acute care spending should be weighted carefully in policy decisions that might impact access to quality health care.

Should All Patients Be Included in Alternative Payment Models for Primary Total Hip Arthroplasty and Total Knee Arthroplasty?

BACKGROUND: Alternative payment models in total joint replacement incentivize cost effective health care delivery and reward reductions in length of stay (LOS), complications, and readmissions. If not adjusted for patient comorbidities, they may encourage restrictive access to health care. METHODS: We prospectively evaluated 802 consecutive primary total hip arthroplasty and total knee arthroplasty patients evaluating comorbidities associated with increased LOS and readmissions. RESULTS: During this 9-month period, 115 patients (14.3%) required hospitalization >3 days and 16 (1.99%) were readmitted within 90 days. Univariate analysis demonstrated that preoperative narcotic use, heart failure, stroke, chronic kidney disease (CKD), chronic obstructive pulmonary disease (COPD), and liver disease were more likely to require hospitalization >3 days. In multivariate analysis, CKD and COPD were independent risk factors for LOS >3 days. A Charlson comorbidity index >5 points was associated with increased LOS and readmissions. CONCLUSION: Patients with CKD, COPD, and Charlson comorbidity index >5 points should not be included in alternative payment model for THA and TKA.

Time dependent analysis of assay comparability: a novel approach to understand intra- and inter-site variability over time.

We demonstrate here a novel use of statistical tools to study intra- and inter-site assay variability of five early drug metabolism and pharmacokinetics in vitro assays over time. Firstly, a tool for process control is presented. It shows the overall assay variability but allows also the following of changes due to assay adjustments and can additionally highlight other, potentially unexpected variations. Secondly, we define the minimum discriminatory difference/ratio to support projects to understand how experimental values measured at different sites at a given time can be compared. Such discriminatory values are calculated for 3 month periods and followed over time for each assay. Again assay modifications, especially assay harmonization efforts, can be noted. Both the process control tool and the variability estimates are based on the results of control compounds tested every time an assay is run. Variability estimates for a limited set of project compounds were computed as well and found to be comparable. This analysis reinforces the need to consider assay variability in decision making, compound ranking and in silico modeling.

Bundled Payment in Total Joint Care: Survey of AAHKS Membership Attitudes and Experience with Alternative Payment Models.

The goal of alternative payment models (APMs), particularly bundling of payments in total joint arthroplasty (TJA), is to incentivize physicians, hospitals, and payers to deliver quality care at lower cost. To study the effect of APMs on the field of adult reconstruction, we conducted a survey of AAHKS members using an electronic questionnaire format. Of the respondents, 61% are planning to or participate in an APM. 45% of respondents feel that a bundled payment system will be the most effective model to improve quality and to reduce costs. Common concerns were disincentives to operate on high-risk patients (94%) and uncertainty about revenue sharing (79%). While many members feel that APMs may improve value in TJA, surgeons continue to have reservations about implementation.

Revision THA in obese patients is associated with high re-operation rates at short-term follow-up.

We performed a retrospective review of 309 consecutive revision THAs from 2005 to 2009. We identified a subgroup of patients with BMI >35 and compared the operative time, rate of complications, ICU admissions, re-admissions, and re-operations to patients with BMI <35 undergoing revision THA. At a mean follow-up of 36.3 months, there was no significant difference in operative time, perioperative complications, or re-admission rate between the two groups. However, a significantly higher rate of re-operation was observed in the obese group (46% vs. 28%, P=0.015). Obese patients were more likely to undergo reoperation for infection (P=0.017). Patients with high BMI contemplating primary THA should be aware of the potential subsequent complications associated with revision surgery should it become necessary.

One-week staged bilateral total knee arthroplasty protocol: a safety comparison of intended and completed surgeries.

The number of patients requiring bilateral total knee arthroplasty (TKA) is expected to grow rapidly. While some trials have compared staged with simultaneous TKA, no literature characterizes the subset of staged TKA patients who cancel their second surgery. In this study, we report on the safety and utility of a one-week staged TKA protocol in a series of 145 patients who registered to undergo staged bilateral total knee arthroplasty one week apart. Among these patients, we identify a significantly higher complication rate and comorbidity status among patients who do not proceed to a second TKA. This finding identifies a potential advantage of a staged protocol over simultaneous bilateral TKA in not subjecting higher-risk patients to a second physiologic insult of a contralateral TKA.