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Background: With the expansion of the Affordable Care Act in 2014, there has been a growing interest in how the Medicaid population will affect postoperative outcomes following total knee arthroplasty (TKA). Studies have shown that lower socioeconomic status, non-Caucasian race, women, cardiac and renal disorders, and younger age have been associated with increased lengths of stay (LOS) after TKA. The primary purpose of our study was to compare the total complications and LOS among patients undergoing TKA who have cash, commercial, government, Medicaid, and Medicare insurances., Methods: We queried a national, all-payer administrative claims database from 2016 to 2022 among patients undergoing TKA who had cash (n = 3,923), commercial (n = 966,169), government (n = 25,644), Medicaid (n = 56,184), and Medicare (n = 524,034) insurances. We compared and analyzed various baseline demographics, total complications, and LOS (<1 day, 1 to 2 days, 3 to 4 days, and >4 days), between the insurance types., Results: Medicaid and Medicaid insurance types had patients who had the most comorbidities at baseline, including a comorbidity index >3 (P < 0.0001), women, alcohol abuse, diabetes, obesity, tobacco use, chronic kidney disease, and congestive heart disease (all P < 0.0001). In accounting for comorbidities, Medicaid was the biggest risk factor for total complications (P < 0.001) as well as increased LOS after TKA at 4 to 6 days, 7 to 9 days, and >9 days (P < 0.0001)., Conclusions: Medicaid insurance is a risk factor for increased total complications and LOS following TKA. Appropriate preoperative and perioperative management of these patients is essential in order to mitigate the risk and burden on the health care system in this population., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: The number of revision total hip arthroplasties (THAs) is projected to reach 572,000 cases annually by 2030 in the United States. This may be attributed to the successes of primary THAs combined with an aging population, patients desire to remain active, and expanded indications for younger patients. Given the evolving nature of revision THAs, an epidemiological analysis of (1) etiologies; (2) demographics, including age and region; and (3) lengths of stay (LOSs) may minimize the gap between appropriate understanding and effective intervention., Methods: From 2016 to 2022, a national, all-payer database was queried. Incidences and indications were analyzed for a total of 102,476 patients who had revision THA procedures. Patients were stratified according to etiology of failure, age, US census region, primary payor class, and mean LOS., Results: The most common etiologies for revision THA procedures were dislocation (16.7%) and infection (12.7%), followed by periprosthetic fracture (6.9%). The largest age group was 65-74 years (30.9%), followed by >75 years (28.6%), then 55-64 (26.5%). The South had the largest total procedure cohort (36.9%), followed by the Midwest (27.5%), then the Northeast (19.7%), and the West (15.9%). The mean LOS was 4.10 days (range, 1.0-20.0)., Conclusions: Dislocation and infection remain leading indications for revision THA. These findings can properly guide surgeons toward appropriate management as well as toward active steps to minimizing these outcomes., (© 2024 The Authors.)

Background: Arthrofibrosis is a debilitating postoperative complication and a major cause of patient dissatisfaction following total knee arthroplasty (TKA). There is no consensus regarding the optimal treatment for stiffness after TKA. For cases not amenable to manipulation under anesthesia (MUA), one component or full revision are both suitable options. In a value-based healthcare era, maximizing cost-effectiveness with optimized clinical outcomes for patients remains the ultimate goal. As such, we compared (1) Knee Injury and Osteoarthritis Outcome Scores for Joint Replacement (KOOS, JR), (2) range of motion (ROM), as well as (3) complication rates, including MUA and lysis of adhesions (LOA), between polyethylene exchange and full component revision for TKA arthrofibrosis., Methods: Patients were queried from an institutional database who underwent revision TKA for arthrofibrosis between January 1, 2015, and April 31, 2021. There were 33 patients who underwent full revision and 16 patients who underwent polyethylene exchange. Demographics and baseline characteristics between the cohorts were analyzed. Postoperative outcomes included MUA, LOA, and re-revision rates as well as KOOS, JR, and extension and flexion ROM at a mean follow-up of 3.8 years. Baseline comorbidities, including age, body mass index, alcohol use, tobacco use, and diabetes, were comparable between the full revision and polyethylene exchange revision cohorts (P > .05). The one and full component revisions had similar preoperative KOOS, JR (43 versus 42, P = .85), and flexion (81 versus 82 degrees, P = .80) versus extension (11 versus 11 degrees, P = .87) ROM., Results: The full component revision had higher KOOS, JR (65 versus 55, P = .04), and flexion (102 versus 92 degrees, P = .02), but similar extension (3 versus 3 degrees, P = .80) ROM at final follow-up compared to the polyethylene exchange revision, respectively. The MUA (18.2 versus 18.8%, P = .96) and LOA (2.0 versus 0.0%, P = .32) rates were similar between full component and polyethylene exchange revisions. There was one re-revision (3.0%) for the cohort of patients who initially underwent full revision. There were four full re-revisions (25.0%) and two polyethylene exchange re-revisions (12.5%) performed in the cohort of patients who initially underwent a polyethylene exchange revision., Conclusions: The full component revision for stiffness after TKA showed favorable KOOS, JR, ROM, and outcomes in comparison to the polyethylene exchange revision. While the optimal treatment for stiffness after TKA is without consensus, this study supports the use of the full component revision when applied to the institutional population at hand. It is imperative that homogeneity exists in preoperative definitions, preoperative baseline patient demographics, ROM and function levels, outcome measures, and preoperative indications, as well as the inclusion of clinical data that assesses complete exchange, single exchange, and tibial insert exchange., (Copyright © 2024. Published by Elsevier Inc.)

Background: In 2021, alternative payment models accounted for 40% of traditional Medicare reimbursements. As such, we sought to examine health disparities through a standardized categorization of social disparity using the social vulnerability index (SVI). We examined (1) risk factors for SVI ≥ 0.50, (2) incidences of complications, and (3) risk factors for total complications between patients who have SVI < 0.50 and SVI ≥ 0.50 who had a total knee arthroplasty (TKA)., Methods: Patients who underwent TKA between January 1, 2022 and December 31, 2022 were identified in the state of Maryland. A total of 4,952 patients who had complete social determinants of health data were included. Patients were divided into 2 cohorts according to SVI: < 0.50 (n = 2,431) and ≥ 0.50 (n = 2,521) based on the national mean SVI of 0.50. The SVI identifies communities that may need support caused by external stresses on human health based on 4 themed scores: socioeconomic status, household composition and disability, minority status and language, and housing and transportation. The SVI theme of household composition and disability encompassed patients aged 65 years and more, patients aged 17 years and less, civilians who have a disability, single-parent households, and English language deficiencies. The higher the SVI, the more social vulnerability or resources are needed to thrive in a geographic area., Results: When controlling for risk factors and patient comorbidities, the theme of household composition and disability (odds ratio 2.0, 95% confidence interval 1.1 to 5.0, P = .03) was the only independent risk factor for total complications. Patients who had an SVI ≥0.50 were more likely to be women (65.8% versus 61.0%, P < .001), Black (34.4% versus 12.9%, P < .001), and have a median household income < $87,999 (21.3% versus 10.2%, P < .001) in comparison to the patients who had an SVI < 0.50, respectively., Conclusions: The SVI theme of household composition and disability, encompassing patients aged 65 years and more, patients aged 17 years and less, civilians who have a disability, single-parent households, and English language deficiencies, were independent risk factors for total complications following TKA. Together, these findings offer opportunities for interventions with selected patients to address social disparities., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: The mode of femoral fixation for primary total hip arthroplasty (THA) is undetermined, with reported outcomes favoring different fixation methods. This study aimed to compare postoperative complications between cemented and cementless fixation at 90 days, 1 year, and 2 years in patients aged 65 years of age and older undergoing THA for osteoarthritis., Methods: Using an all-payer, national database, patients 65 years and older undergoing primary THA, either with cementless (n = 56,701) or cemented (n = 6,283) femoral fixation for osteoarthritis were identified. A 1:1 propensity-matched analysis for age, sex, comorbidity index, alcohol abuse, tobacco use, obesity, and diabetes was performed, resulting in n = 6,283 patients in each cohort. Postoperative outcomes, including postoperative periprosthetic joint infection, aseptic revision, surgical site infection, pulmonary embolism, venous thromboembolism, wound complications, dislocation, periprosthetic fracture, and aseptic loosening were assessed., Results: The cemented cohort had higher rates of infection (4.5 versus 0.8%, odds ratio [OR] 5.9, 95% confidence interval [CI] 4.33 to 7.93, P < .001), aseptic revision (2.9 versus 2.0%, OR 1.47, 95% CI 1.17 to 1.85, P = .001), venous thromboembolism (1.8 versus 1.3%, OR 1.40, 95% CI 1.05 to 1.87, P < .001), and aseptic loosening (1.5 versus 0.7%, OR 2.31, 95% CI 1.60 to 3.32, P < .001) at 90-days. At 1 and 2 years, the cemented cohort had higher rates of infection, aseptic revision, and aseptic loosening (all P < .001). Rates of periprosthetic fracture were similar at all time points (all P < .001)., Conclusions: Cemented fixation had higher rates of infection, aseptic loosening, and aseptic revision. This finding supports the current use of cementless fixation, but the ultimate decision regarding fixation type should be based on the proper optimization of the patient's comorbidities and bone quality., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Vulnerable populations, including patients from a lower socioeconomic status, are at an increased risk for infection, revision surgery, mortality, and complications after total joint arthroplasty (TJA). An effective metric to quantify and compare these populations has not yet been established in the literature. The Area Deprivation Index (ADI) provides a composite area-based indicator of socioeconomic disadvantage consisting of 17 U.S. Census indicators, based on education, employment, housing quality, and poverty. We assessed patient risk factor profiles and performed multivariable regressions of total complications at 30 days, 90 days, and 1 year., Methods: A prospectively collected database of 3,024 patients who underwent primary elective total knee arthroplasty or total hip arthroplasty performed by 3 fellowship-trained orthopaedic surgeons from January 1, 2015, through December 31, 2021, at a tertiary health-care center was analyzed. Patients were divided into quintiles (ADI ≤20 [n = 555], ADI 21 to 40 [n = 1,001], ADI 41 to 60 [n = 694], ADI 61 to 80 [n = 396], and ADI 81 to 100 [n = 378]) and into groups based on the national median ADI, ≤47 (n = 1,896) and >47 (n = 1,128)., Results: Higher quintiles had significantly more females (p = 0.002) and higher incidences of diabetes (p < 0.001), congestive heart failure (p < 0.001), chronic obstructive pulmonary disease (p < 0.001), hypertension (p < 0.001), substance abuse (p < 0.001), and tobacco use (p < 0.001). When accounting for several confounding variables, all ADI quintiles were not associated with increased total complications at 30 days, but age (p = 0.023), female sex (p = 0.019), congestive heart failure (p = 0.032), chronic obstructive pulmonary disease (p = 0.001), hypertension (p = 0.003), and chronic kidney disease (p = 0.010) were associated. At 90 days, ADI > 47 (p = 0.040), female sex (p = 0.035), and congestive heart failure (p = 0.001) were associated with increased total complications., Conclusions: Balancing intrinsic factors, such as patient demographic characteristics, and extrinsic factors, such as social determinants of health, may minimize postoperative complications following TJA. The ADI is one tool that can account for several extrinsic factors, and can thus serve as a starting point to improving patient education and management in the setting of TJA., Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: No external funding was received for the work. The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJSOA/A616)., (Copyright © 2024 The Authors. Published by The Journal of Bone and Joint Surgery, Incorporated. All rights reserved.)

Purpose: There is consensus in favor of a description of the dorsal ligaments of the carpus as not including a direct ligament between the lunate and capitate. On the other hand, there is an anatomical formation which, according to the currently accepted description, corresponds to the dorsal midcarpal capsule, itself thickened by the dorsal intercarpal ligament. The question is whether the capsule at this point deserves to be called an individualizable ligament. In our operative experience of the dorsal carpus, we have encountered a stout structure adherent to the lunate and capitate. In this article, we present the anatomic evidence of this structure's existence., Methods: Seven adult fresh frozen upper extremities were dissected. Three wrists were longitudinally sectioned in line with the middle finger metacarpal. The remaining 4 were dissected dorsally. Two representative samples of the stout structure connecting the lunate to the capitate were sent to pathology for histologic analysis and staining., Results: In all 3 of the longitudinally sectioned wrists, a thick band of tissue could clearly be seen, originating on the lunate, spanning the dorsal interval between the lunate and the capitate, and inserting on the capitate. With this structure intact, dorsal dislocation of the capitate was not possible, but preliminary sectioning of the structure allowed dislocation. In the 4 dorsally dissected wrists, the same connection was observed, palmar to the dorsal intercarpal ligament, in every specimen. The average dimensions of the dorsal capitolunate were: 15.25 ± 1 mm long, 8.75 ± 1 mm wide at the midpoint, and 1.75 ± 1 mm thick. The two specimens sent to pathology after sectioning showed longitudinally oriented collagen fibers. This structure also stained positive for elastin and contained intrasubstance vascular structures., Conclusion: There is a stout ligamentous structure connecting the lunate to the capitate, palmar to the dorsal intercarpal ligament. Disruption of this structure appears to be necessary for dorsal dislocation of the capitate. Clinical studies are needed to gain better understanding of the exact function and importance of this structure., (Copyright © 2024 SFCM. Published by Elsevier Masson SAS. All rights reserved.)

Introduction: Complex proximal humerus fractures pose challenges in elderly patients, as this common scenario can lead to unpredictable outcomes, regardless of treatment method. Given the evolving nature of the treatment for 3-and-4-part proximal humerus fractures, an epidemiological analysis offers a way to minimize the gap between appropriate understanding and effective intervention. As such, we aimed to i) evaluate the trends of nonoperative and operative management; and ii) compare the complication rates of ORIF to conversion ORIF (to RTSA)., Methods: We utilized a national, all-payer database to include patients who underwent open reduction and internal fixation for 2-part (n = 2783), 3-part (n = 2170), 4-part (n = 1087) proximal humerus fractures between April 2016 to December 2022. Patients who failed ORIF to RTSA included n = 108 for 2-part fractures, n = 123 for 3-part fractures, and n = 128 for 4-part fractures. We collected demographic and postoperative medical and surgical complications at 90-days, in addition to time-interval between ORIF and RTSA., Results: The malunion and nonunion rates for ORIF between different types of proximal humerus fractures were similar (2-part fractures: 1.8 %, 4.7 %; 3-part fractures: 1.8 %, 3.5 %; 4-part fractures: 2.4 %, 3.7 %). The conversion rates of failed ORIF to RTSA were 1.9 %, 2.8 %, and 5.9 % for 2-part, 3-part, and 4-part fractures, respectively. The time interval from failed ORIF to RTSA was 190 days for 2-part fractures, 169 days for 3-part fractures, and 129 for 4-part fractures., Conclusion: An epidemiological analysis of proximal humerus fractures by fracture type demonstrated an increase in RTSA for 2-part, 3-part, and 4-part fractures while nonoperative treatment showed no change from 2016 to 2020. Additional research is needed to determine which fractures are best treated operatively while maximizing outcomes. In the setting of complex proximal humerus fractures, several options seem feasible depending on patient demographic characteristics., Competing Interests: SSB- None. JAD- None. EAR-None. RG- None. DH-None. RM- None. JVI- None., (© 2023 Professor P K Surendran Memorial Education Foundation. Published by Elsevier B.V. All rights reserved.)

Introduction: Traditional total knee arthroplasty (TKA) designs fail to reproduce physiologic knee kinematics, which can contribute to patient dissatisfaction. In an attempt to restore more normal knee kinematics, the medial pivot (MP) design may improve knee function and stability as well as patient satisfaction. A limited number of studies have compared postoperative outcomes of exclusively cementless Cruciate-Retaining (CR) TKAs to cementless MP TKAs. We aimed to compare: (1) 90-day, 1-year, and 2-year complications and revisions, (2) preoperative and postoperative range of motion (ROM), (3) Knee Injury and Osteoarthritis Outcome (KOOS-JR), and (4) visual analog scale (VAS) pain scores at 3-month, 6-month, 1-year, and 2-years., Methods: A retrospective analysis was performed to identify all patients who had previously undergone a TKA at our institution and compare a cementless CR system to a cementless MP design. Categorical variables, including demographics, comorbidities, and complications utilized Chi -square tests in bivariable analysis. Continuous variables, such as age, were compared using Student's t -tests. Significance was defined as p  < 0.05., Results: Cementless CR and cementless MP cohorts showed low profiles of postoperative complications and favorable patient-reported outcome measures (PROMs). The MP cohort had lower VAS pain at 1-year (1.70 vs. 3.76, p < 0.001) and 2-years (1.43 vs. 2.60, p < 0.001) and higher ROM at 3-months (118 vs. 100, p < 0.001), 6-months (113 vs. 103, p < 0.0001), and 1-year (117 vs. 110, p = 0.02), respectively., Conclusion: This study is the first comparison of postoperative outcomes between a cementless CR TKA and cementless MP TKA designs. Implant design and fixation type are vital components influencing patient satisfaction after TKA. Pain scores and range of motion favored the cementless MP cohort in comparison to the cementless CR cohort., (© 2023 Published by Elsevier B.V. on behalf of Professor P K Surendran Memorial Education Foundation.)

Background: As legalization of cannabis spreads, an increasing number of patients who use cannabis are being seen in the clinical setting. This study examined the impact of cannabis and tobacco use on postoperative complications following open reduction and internal fixation (ORIF) of distal radius fractures., Methods: A national, all-payer database was queried to identify patients who underwent ORIF of a distal radius fracture between 2015 and 2020 (n = 970 747). Patients were stratified into the following groups: (1) tobacco use (n = 86 941), (2) cannabis use (n = 898), (3) tobacco and cannabis use (n = 9842), and (4) neither tobacco nor cannabis use ("control", 747 892). Multivariable logistic regression was used to identify risk factors for infection, nonunion, and malunion within the first postoperative year., Results: Concomitant use of tobacco and cannabis was associated with a higher rate of nonunion (5.0%) compared to tobacco or cannabis use alone ( P < .001). Multivariate analysis identified cannabis-only use (odds ratio [OR] 1.25), tobacco-only use (OR 2.17), and concurrent tobacco and cannabis use (OR 1.78) as risk factors for infection within the first postoperative year. Similarly, cannabis-only use (OR 1.47), tobacco-only use (OR 1.92), and concurrent tobacco and cannabis use (OR 2.52) were associated with an increased risk of malunion., Conclusions: Cannabis use is associated with an elevated risk of infection and malunion following operative management of a distal radius fracture. Concomitant use of cannabis and tobacco poses an elevated risk of nonunion and malunion compared to tobacco use alone., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Trigger finger may be treated with open surgical release. Local corticosteroid injections have also demonstrated success. Studies suggest recipients of flexor sheath corticosteroid up to 90-days prior to open surgery are at increased risk of post-operative infection. However, the possible link between large joints corticosteroid prior to trigger finger release remains unexplored. Therefore, this study aimed to provide complication risks for trigger finger release recipients after large joint corticosteroid., Methods: We reviewed a national, all-payer database and examined patients who did not receive and did receive corticosteroid two, four, or six weeks prior to trigger finger release. Primary outcomes assessed were 90-day risk for antibiotics, infection, and irrigations and debridement. Multivariate logistic analyses compared cohorts using odds ratios with 95% confidence intervals., Results: No trends were found regarding antibiotic requirements, infection, as well irrigations and debridement within 90-days for recipients of corticosteroid into large joints two, four, or six weeks prior to open trigger finger release. Elixhauser Comorbidity Index, alcohol abuse, diabetes mellitus, and tobacco use were identified as independent risks for requiring antibiotics as well as irrigations and debridement (all Odds Ratios > 1.06, all p ≤ 0.048)., Conclusions: Patients who underwent trigger finger release after receiving a corticosteroid into a large joint two, four, or six weeks prior has no association with 90-day antibiotics, infection, or irrigations and debridement. While the comfort levels for individual surgeons vary, optimizing these comorbidities prior to surgery is an important goal discussed with patients to lower risks for infections., Retrospective: Level III., (Copyright © 2023 SFCM. Published by Elsevier Masson SAS. All rights reserved.)

Use of mobile applications to improve patient engagement is particularly promising in total joint arthroplasty (TJA) whereby successful outcomes are predicated by patient engagement. In accordance with published guidelines by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, studies were searched, screened, and appraised for quality on various search engines. Hedges' g or odds ratios of patient adherence were reported. Twelve studies met the inclusion criteria, and the average age of 9,521 patients included was 60 years. Six studies concluded that mobile applications improved patients' satisfaction, with Hedges' g revealing an effect size of 1.64 (95% confidence interval [CI] 0.90 to 2.37), P < 0.001, in favor of mobile applications increasing patient satisfaction. Six studies reported improvements in compliance demonstrating an odds ratio for improved adherence of 4.57 (95% CI, 1.66 to 12.62), P < 0.001. Two studies reported a reduction in unscheduled office or emergency department visits. With evolving reimbursement policies linked to outcomes paired with the exponentially increasing volume of TJA performed, innovative ways to efficiently deliver high-quality care are in demand. Our systematic review is limited by a dearth of research on the nascent technology, but the available data suggest that mobile applications may enhance patient satisfaction, improve compliance, and reduce unscheduled visits after TJA., (Copyright © 2023 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Orthopaedic Surgeons.)

Background: Despite the fact that patients with chronic liver disease (CLD) are at increased risk of complications after a fracture of the hip, there remains little information about the risk factors for acute postoperative complications and their overall outcome.The aim of this study was to describe inpatient postoperative complications and identify predictors of postoperative morbidity., Methods: Patients with CLD who had been treated for a fracture of the hip between April 2005 and August 2019 were identified from a retrospective search of an intramural trauma registry based in the Northeastern United States. Medical records were reviewed for baseline demographics, preoperative laboratory investigations, and outcomes., Results: The trauma registry contained 110 patients with CLD who had undergone surgery for a fracture of the hip. Of these, patients with a platelet-count of ⩽100,000/µL were 3.81 (95% CI, 1.59-9.12) times more likely to receive a transfusion than those with a platelet-count of >100,000/µL. Those with a Model for End-stage Liver Disease (MELD) score of >9 were 5.54 (2.33-13.16) times more likely to receive a transfusion and 3.97 (1.06-14.81) times more likely to develop postoperative delirium than those with a MELD score of ⩽9.Of patients without chronic kidney disease, those with a creatinine of ⩾1.2 mg/dL were 6.80 (1.79-25.87) times more likely to develop acute renal failure (ARF) than those with a creatinine of <1.2 mg/dL. In a multivariable model, as MELD score was increased, the odds of developing a composite postoperative complication, which included transfusion, ARF, delirium, or deep wound infection, were 1.29 (1.01-1.66). Other tools used to assess surgical risks, Charlson Comorbidity Index, Elixhauser, and American Society of Anesthesiologist scores, were not predictive., Conclusions: Patients with CLD who undergo surgery for a hip fracture have a high rate of postoperative complications which can be predicted by the preoperative laboratory investigations identified in this study and MELD scores, but not by other common comorbidity indices.

Various surgical techniques exist to treat de Quervain's stenosing tendovaginitis. Specific surgical techniques for de Quervain's are designed to avoid complications including injury to branches of the superficial branch of the radial nerve, inadequate decompression, reflex sympathetic dystrophy, and palmar subluxation of the released tendons. A simple dorsal incision through the extensor retinaculum is advocated by many as a means to release the compartment while preventing postoperative subluxation. A single incision through the retinaculum limits exposure of the compartment and could lead to reannealing of the retinaculum and recurrent symptoms. Partial resection of the extensor retinaculum provides a more complete release and has not been found to lead to palmar tendon subluxation., Competing Interests: Conflicts of Interest and Source of Funding: The authors report no conflicts of interest and no source of funding., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Poor metaphyseal fixation secondary to bone loss in revision total knee arthroplasty (TKA) continues to be challenging. One technique to increase implant stability is the use of novel three-dimensional (3D) printed titanium metaphyseal cones with adjunctive stems for added fixation. However, the survival of these novel constructs is poorly understood. Therefore, we sought to examine 3D-printed titanium metaphyseal cone components in revision TKA for aseptic as well as septic reasons and aimed to evaluate: (1) revision-free survivorships; (2) patient-reported outcomes measures (PROMs); (3) postoperative medical complications; and (4) radiographic outcomes. A consecutive series of 62 patients who underwent revision TKA with use of a titanium metaphyseal cone at a single institution between September 1, 2015 and May 31, 2021 were examined. The patients had a minimum follow-up period of 2 years (mean, 40 months, range, 24-72 months). PROMS included Knee Injury and Osteoarthritis Outcome Score Joint Replacement (KOOS-JR) scores at baseline and last clinical follow-up. Overall, when excluding infections, the combined implant survivorship was 96% (52 out of 54), while it was 95% (35 out of 57) for aseptic revisions and 100% (17 out of 17) for septic revisions. Reasons for revisions within the aseptic revision cohort included loosening (5%) as well as periprosthetic joint infections (PJIs) (7.5%). All failures following an index septic revision were due to PJI. Mean KOOS scores at baseline as well as at final follow-up was 43 points (range, 16-80) and 70 points (range, 34-100), respectively. None of the patients had medical complications. Other than the loosening reported (only femoral component), of the surviving patients no patients had evidence of progressive radiolucencies. The use of titanium cones in revision TKA provides good revision-free survivorship at 2 years. Further research is warranted on the longer-term survivorship of 3D-printed titanium cones. The current study has found that 3D-printed titanium cones can be incorporated as part of the revision knee surgeon's armamentarium., Competing Interests: None declared., (Thieme. All rights reserved.)

There is renewed interest in performing arthroscopic anterior cruciate ligament (ACL) repairs in appropriate patients who have Sherman type 1 ACL tears. However, ACL repairs are associated with unacceptably high failure rates, which may be partly improved with suture augmentation. Our technique uses a hamstring autograft tendon to reconstruct a bundle through a femoral tunnel while inserting the native ACL tissue into the other bundle's femoral footprint. The tear pattern dictates whether the native ACL tissue is inserted into the anteromedial or posterolateral lateral femoral origin. The improved cellular and biomechanical milieu for healing of both the repair and reconstruction may translate to earlier return to sport and reduced failure rates. In addition, by restoring the entire femoral footprint with a single femoral tunnel, improved rotational control is achieved without the bone stock loss observed in traditional ACL double-bundle reconstruction.

Background: Patient compliance with perioperative protocols is paramount to improving outcomes and reducing adverse events in total joint arthroplasty (TJA) of the hip and knee. Given the widespread use of smartphones, mobile applications (MAs) may present an opportunity to improve outcomes in TJA. We aim to determine whether the use of a mobile application platform improves compliance with standardized pre-operative protocols and outcomes in TJA., Methods: A non-randomized, prospective cohort study was conducted in adult patients undergoing primary elective TJA to determine whether the use of an MA with timed reminders starting 5 days pre-operatively, to perform a chlorhexidine gluconate (CHG) shower and oral hydration protocol improves compliance with these protocols., Outcome Measures: compliance, length of stay (LOS), surgical site infection (SSI), 90-day readmission., Results: App-users had increased adherence to the hydration protocol (odds ratio [OR] = 3.17 [95% confidence interval {CI} = 1.42, 7.09: P = .003]). App-use was associated with shorter LOS (Median Interquartile ranges [IQR] 2.0 days [1.0, 2.0 days]) for App-users vs 2.0 days ([1.0, 3.0] for non-App users, P = .031), younger age, (63.3 vs 67.9 years, P = .0001), Caucasian race (OR = 3.32 [95% CI = 1.59, 6.94 P = .0009]) and male gender (48.2% vs 35.0%, P = .02). There was no difference in adherence to chlorhexidine gluconate (CHG), readmission, or surgical site infection (SSI) (2.2% App-users vs 2.9% non-App users; P = .74)., Conclusion: Use of a mobile application was associated with increased compliance with a hydration protocol and reduced LOS. App-users were more likely to be younger, male and Caucasian. These disparities may reflect inequity of access to the requisite technology and warrant further study., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Preoperative calculation of treatment failure risk in patients undergoing surgery for periprosthetic joint infection (PJI) is imperative to allow for medical optimization and targeted prevention. A preoperative prognostic model for PJI treatment failure was previously developed, and this study sought to externally validate the model., Methods: A retrospective review was performed of 380 PJIs treated at two institutions. The model was used to calculate the risk of treatment failure, and receiver operating characteristic curves were generated to calculate the area under the curve (AUC) for each institution., Results: When applying this model to institution 1, an AUC of 0.795 (95% confidence interval [CI]: 0.693-0.897) was found, whereas institution 2 had an AUC of 0.592 (95% CI: 0.502-0.683). Comparing all institutions in which the model had been applied to, we found institution 2 represented a significantly sicker population and different infection profile., Conclusion: In this cohort study, we externally validated the prior published model for institution 1. However, institution 2 had a decreased AUC using the prior model and represented a sicker and less homogenous cohort compared with institution 1. When matching for chronicity of the infection, the AUC of the model was not affected. This study highlights the impact of comorbidities and their distributions on PJI prognosis and brings to question the clinical utility of the algorithm which requires further external validation., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Objective: Plasmids are key to antimicrobial resistance transmission among enteric bacteria. It is becoming increasingly clear that resistance genes alone do not account for the selective advantage of plasmids and bacterial strains that harbor them. Deletion of a 32 Kb fitness-conferring region of pMB2, a conjugative resistance plasmid, produced a hyper-autoaggregation phenotype in laboratory Escherichia coli. This study sought to determine the genetic basis for hyper-autoaggregation conferred by the pMB2-derived mini-plasmid., Results: The 32 Kb fragment deleted from pMB2 included previously characterized nutrient acquisition genes as well as putative transposase and integrase genes, a 272 bp papB/ pefB-like gene, and several open-reading frames of unknown function. We cloned the papB/ pefB paralogue and found it sufficient to temper the hyper-autoaggregation phenotype. Hyper-autoaggregation conferred by the mini-plasmid did not occur in a fim-negative background. This study has identified and characterized a gene capable of down-regulating host adhesins and has shown that trans-acting papB/pefB paralogues can occur outside the context of an adhesin cluster. This plasmid-mediated modification of a bacterial host's colonization program may optimize horizontal transfer of the mobile element bearing the genes.

Antimicrobial resistance is rapidly expanding, in a large part due to mobile genetic elements. We screened 94 fecal fluoroquinolone-resistant Escherichia coli isolates from Nigeria for six plasmid-mediated quinolone resistance (PMQR) genes. Sixteen isolates harbored at least one of the PMQR genes and four were positive for aac-6-Ib-cr. In one strain, aac-6-Ib-cr was mapped to a 125 Kb self-transmissible IncFII plasmid, pMB2, which also bears bla CTX-M-15 , seven other functional resistance genes and multiple resistance pseudogenes. Laboratory strains carrying pMB2 grew faster than isogenic strains lacking the plasmid in both rich and minimal media. We excised a 32 Kb fragment containing transporter genes and several open-reading frames of unknown function. The resulting 93 Kb mini-plasmid conferred slower growth rates and lower fitness than wildtype pMB2. Trans-complementing the deletion with the cloned sitABCD genes confirmed that they accounted for the growth advantage conferred by pMB2 in iron-depleted media. pMB2 is a large plasmid with a flexible resistance region that contains loci that can account for evolutionary success in the absence of antimicrobials. Ancillary functions conferred by resistance plasmids can mediate their retention and transmissibility, worsening the trajectory for antimicrobial resistance and potentially circumventing efforts to contain resistance through restricted use.

Expression of the quinolone resistance gene qnrS1 is increased by quinolones, but unlike induction of some other qnr genes, the bacterial SOS system is not involved and no lexA box is found upstream. Nonetheless, at least 205 bp of upstream sequence is required for induction to take place. An upstream sequence bound to beads trapped potential binding proteins from cell extracts that were identified by mass spectrometry as Dps, Fis, Ihf, Lrp, CysB, and YjhU. To further elucidate their role, a reporter plasmid linking the qnrS1 upstream sequence to lacZ was introduced into cells of the Keio collection with single-gene deletions and screened for lacZ expression. Mutants in ihfA and ihfB had decreased lacZ induction, while induction in a cysB mutant was increased and dps , fis , lrp , yjhU , and other mutants showed no change. The essential upstream sequence contains potential binding sites for Ihf and DnaA. A dnaA deletion could not be tested because it provides essential functions in cell replication; however, increased dnaA expression decreased qnrS1 induction while decreased dnaA expression enhanced it, implying a role for DnaA as a repressor. In a mobility shift assay, purified IhfA, IhfB, and DnaA proteins (but not CysB) were shown to bind to the upstream segment. Induction decreased in a gyrA quinolone-resistant mutant, indicating that GyrA also has a role. Thus, quinolones acting through proteins DnaA, GyrA, IhfA, and IhfB regulate expression of qnrS1 ., (Copyright © 2018 American Society for Microbiology.)

Background: Kelsh et al. [2007]: Occup Med (Lond) 57:581-589 published a paper reanalyzing one of the few data sources publicly available on mesothelioma amongst brake workers, the Australian Mesothelioma Surveillance Registry (AMSR). This reanalysis was commissioned by lawyers representing the automobile manufacturing companies and did not align with an independent analysis published by Leigh and Driscoll [2003]: Occup Environ Health 9:206-217., Methods: We sought to reevaluate the AMSR data ourselves to understand how the company-sponsored research categorized the data., Results: In our re-analysis of the 78 brake-related folios in the AMSR, we determined that 57 were employed brake mechanics, 35 were employed brake mechanics with no other asbestos exposure besides brake work or repair, and 41 of these cases had no other asbestos exposure besides brake work or repair. Our classifications differed significantly from Kelsh et al., Conclusions: We discuss how Kelsh et al. methodically reduced the relevant cases by following overly stringent criteria for inclusion. Am. J. Ind. Med. 60:152-162, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)