Vaccines: Do they have a role in orthopedic trauma?

Although vaccines have been hailed as one of the greatest advances in medicine based on their unparalleled cost-effectiveness in eradicating life-threatening infectious diseases, their role in orthopedic trauma-related infections is unclear. This is largely because vaccines are primarily made against pathogens that cause communicable diseases rather than opportunistic infections secondary to trauma, and most successful vaccines are against viruses rather than biofilm forming bacteria. Nonetheless, the tremendous costs to patients and healthcare systems warrant orthopedic trauma vaccine research, which has been a focal topic in recent international consensus meetings on musculoskeletal infection. This subject was also covered at the 2023 Osteosynthesis and Trauma Care Foundation (OTCF) meeting in Rome, Italy, and the purpose of this supplement article is to (1) highlight the osteoimmunology, animal models, translational research and clinical pilots that were discussed, (2) the proposed future directions that could lead to diagnostics and prognostics that are critically needed for evidence-based decision making, and (3) vaccines and passive-immunization strategies that could potentially be utilized to treat patients with orthopedic infections.

Update on Atypical Femoral Fractures.

➤ Atypical femoral fractures (AFFs) are stress fractures between the lesser trochanter and the metaphyseal flare that are most commonly related to prolonged (3 to 5 years) antiresorptive medication use.➤ An important finding is a visible transverse line in the lateral cortex, known as the "dreaded black line." Complete fractures are transverse and have minimal comminution.➤ Prodromal symptoms including hip, groin, thigh, and knee pain are present in more than one-half of cases and are usually misdiagnosed.➤ Nonoperative treatment for all patients with AFF includes withdrawal of bisphosphonates, assessment for secondary causes of osteoporosis, and optimization of vitamin D and calcium.➤ Incomplete fractures without a visible line can initially be treated nonoperatively with protected weight-bearing.➤ Intramedullary nailing is indicated for complete fractures and incomplete fractures with a visible fracture line. Delayed healing after fixation should be anticipated.➤ Treatment with parathyroid hormone (PTH) analogs (teriparatide and abaloparatide) after AFF prevents other fractures in high-risk patients, but the effect on healing of the fracture is unclear.

Dilution of humoral immunity: Results from a natural history study of healthy total knee arthroplasty patients.

The incidence of prosthetic joint infection (PJI) following elective primary total knee arthroplasty (TKA) is very low but serious risk remains. To identify unknown risk factors, we completed a natural history study of IgG specific for Staphylococcus aureus antigens previously phenotyped as protective (anti-Atl) and pathogenic (anti-Isd). Twenty-five male and 25 female optimized patients 50-85 years of age and BMI 24-39 undergoing primary TKA were prospectively enrolled. Blood sampling was performed preoperatively, postoperative Day 1, and at 2, 6, and 12 weeks, to assess serum cytokine, anti-staphylococcal IgG levels and anti-tetanus toxoid IgG measured via custom Luminex assay. Clinical, demographic, and PROMIS-10 data were collected with outcomes to 2 years postop. All participants completed the study and 2-year follow-up. No patients were readmitted or noted to develop a surgical site infection or serious adverse event, and patient-reported outcomes were improved. Serology revealed a highly significant decrease in six out of eight antibody titers against specific S. aureus antigens on Day 1 (p < 0.0001), five of which normalized to preoperative levels within 2 weeks. These changes were commensurate with a decrease and recovery of anti-tetanus toxoid titers, and a 20% drop in hemoglobin 13.8 ± 1.7 at preop to 11.1 ± 1.8 mg/dL on Day 1 (p < 0.0001). After TKA, a significant decrease in humoral immunity commensurate with blood loss and hemodilution was recorded. This decrease in circulating anti-staphylococcal antibodies in the early postop period may represent a periprosthetic joint infection risk factor for patients.

Early Complications of a Novel Retrograde Intramedullary Femoral Nail in the Treatment of Femur Fractures.

OBJECTIVES: To determine the early implant failure rate of a novel retrograde intramedullary femoral nail. DESIGN: Retrospective cohort study. SETTING: Academic level 1 trauma center. PATIENTS SELECTION CRITERIA: Patients aged 18 years and older with an acute OTA/AO 32-A, 32-B, 32-C, and 33-A fractures or periprosthetic distal femur fracture from April 2018 to April 2022 were included in the study. The 2 interventions compared were the Synthes Expert retrograde/antegrade femoral nail (or control implant) versus the next-generation retrograde femoral nail (RFN)-advanced retrograde femoral nail (RFNA or experimental implant) (Synthes, West Chester, PA). OUTCOME MEASURES AND COMPARISONS: Early implant-related complications between the experimental and control implants were assessed including locking screw back out, screw breakage, intramedullary nail failure, need for secondary surgery, and loss of fracture reduction. RESULTS: Three hundred fourteen patients were identified with a mean age of 31.0 years, and 62.4% of the patients being male. Open fractures occurred in 32.5% of patients with 3.8% of injuries being distal femur periprosthetic fractures. Fifty-six patients were in the experimental group and 258 patients in the control group. Mean follow-up was 46.8 weeks for the control cohort and 21.0 weeks for the experimental cohort. Distal interlocking screw back out occurred in 23.2% (13 of 56) of the experimental group patients and 1.9% (5 of 258) of the control group patients ( P < 0.0001). Initial diagnosis of interlocking screw back out occurred at an average of 3.2 weeks postoperatively (range, 2-12 weeks). Fifty-four percent of patients who sustained screw back out underwent a secondary operation to remove the symptomatic screws (12.5% of all patients treated with the experimental implant required an unplanned secondary operation due to screw back out). A logistic regression model was used to predict screw back out and found the experimental implant group was 4.3 times as likely to experience distal locking screw back out compared with the control group ( P = 0.01). CONCLUSIONS: The retrograde femoral nail-advanced implant was associated with a significantly higher rate of screw back out with a substantial number of unplanned secondary surgeries compared with the previous generation of this implant. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Geriatric trauma: there is more to it than just the implant!

Geriatric trauma continues to rise, corresponding with the continuing growth of the older population. These fractures continue to expand, demonstrated by the incidence of hip fractures having grown to 1.5 million adults worldwide per year. This patient population and their associated fracture patterns present unique challenges to the surgeon, as well as having a profound economic impact on the health care system. Pharmacologic treatment has focused on prevention, with aging adults having impaired fracture healing in addition to diminished bone mineral density. Intraoperatively, novel ideas to assess fracture reduction to facilitate decreased fracture collapse have recently been explored. Postoperatively, pharmacologic avenues have focused on future fracture prevention, while shared care models between geriatrics and orthopaedics have shown promise regarding decreasing mortality and length of stay. As geriatric trauma continues to grow, it is imperative that we look to optimize all phases of care, from preoperative to postoperative.

Longitudinal intravital imaging of the bone marrow for analysis of the race for the surface in a murine osteomyelitis model.

Critical knowledge gaps of orthopedic infections pertain to bacterial colonization. The established dogma termed the Race for the Surface posits that contaminating bacteria compete with host cells for the implant post-op, which remains unproven without real-time in vivo evidence. Thus, we modified the murine longitudinal intravital imaging of the bone marrow (LIMB) system to allow real-time quantification of green fluorescent protein (GFP+) host cells and enhanced cyan fluorescent protein (ECFP+) or red fluorescent protein (RFP+) methicillin-resistant Staphylococcus aureus (MRSA) proximal to a transfemoral implant. Following inoculation with ~105 CFU, an L-shaped metal implant was press-fit through the lateral cortex at a 90° angle ~0.150 mm below a gradient refractive index (GRIN) lens. We empirically derived a volume of interest (VOI) = 0.0161 ± 0.000675 mm3 during each imaging session by aggregating the Z-stacks between the first (superior) and last (inferior) in-focus LIMB slice. LIMB postimplantation revealed very limited bacteria detection at 1 h, but by 3 h, 56.8% of the implant surface was covered by ECFP+ bacteria, and the rest were covered by GFP+ host cells. 3D volumetric rendering of the GFP+ and ECFP+ or RFP+ voxels demonstrated exponential MRSA growth between 3 and 6 h in the Z-plane, which was validated with cross-sectional ex vivo bacterial burden analyses demonstrating significant growth by ~2 × 104 CFU/h on the implant from 2 to 12 h post-op (p < 0.05; r2 > 0.98). Collectively, these results show the competition at the surface is completed by 3 h in this model and demonstrate the potential of LIMB to elucidate mechanisms of bacterial colonization, the host immune response, and the efficacy of antimicrobials.

The 2023 Orthopaedic Research Society's International Consensus Meeting on musculoskeletal infection: Summary from the host immunity section.

Musculoskeletal infections (MSKI), which are a major problem in orthopedics, occur when the pathogen eludes or overwhelms the host immune system. While effective vaccines and immunotherapies to prevent and treat MSKI should be possible, fundamental knowledge gaps in our understanding of protective, nonprotective, and pathogenic host immunity are prohibitive. We also lack critical knowledge of how host immunity is affected by the microbiome, implants, prior infection, nutrition, antibiotics, and concomitant therapies, autoimmunity, and other comorbidities. To define our current knowledge of these critical topics, a Host Immunity Section of the 2023 Orthopaedic Research Society MSKI International Consensus Meeting (ICM) proposed 78 questions. Systematic reviews were performed on 15 of these questions, upon which recommendations with level of evidence were voted on by the 72 ICM delegates, and another 12 questions were voted on with a recommendation of "Unknown" without systematic reviews. Two questions were transferred to another ICM Section, and the other 45 were tabled for future consideration due to limitations of available human resources. Here we report the results of the voting with internet access to the questions, recommendations, and rationale from the systematic reviews. Eighteen questions received a consensus vote of ≥90%, while nine recommendations failed to achieve this threshold. Commentary on why consensus was not achieved on these questions and potential ways forward are provided to stimulate specific funding mechanisms and research on these critical MSKI host defense questions.

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

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

Epidemiological updates of post-traumatic related limb osteomyelitis in china: a 10 years multicentre cohort study.

BACKGROUND: Post-traumatic related limb osteomyelitis (PTRLO) is a complex bone infection. Currently, there are no available microbial data on a national scale that can guide appropriate antibiotic selection, and explore the dynamic changes in dominant pathogens over time. This study aimed to conduct a comprehensive epidemiological analysis of PTRLO in China. METHODS: The study was approved by the Institutional Research Board (IRB), and 3526 PTRLO patients were identified from 212 394 traumatic limb fracture patients at 21 hospitals between 1 January 2008 and 31 December 2017. A retrospective analysis was conducted to investigate the epidemiology of PTRLO, including changes in infection rate (IR), pathogens, infection risk factors and antibiotic resistance and sensitivity. RESULTS: The IR of PTRLO increased gradually from 0.93 to 2.16% (Z=14.392, P <0.001). Monomicrobial infection (82.6%) was significantly higher than polymicrobial infection (17.4%) ( P <0.001). The IR of Gram-positive (GP) and Gram-negative (GN) pathogens showed a significant increase from the lowest 0.41% to the highest 1.15% (GP) or 1.62% (GN), respectively. However, the longitudinal trend of GP vs. GN's composition did not show any significance (Z=±1.1918, P >0.05). The most prevalent GP strains were Methicillin-sensitive Staphylococcus aureus (MSSA) (17.03%), Methicillin-resistant Staphylococcus aureus (MRSA) (10.46%), E. faecalis (5.19%) and S. epidermidis (4.87%). In contrast, the dominant strains GN strains were Pseudomonas Aeruginosa (10.92%), E. cloacae (10.34%), E. coli (9.47%), Acinetobacter Baumannii (7.92%) and Klebsiella Pneumoniae (3.33%). In general, the high-risk factors for polymicrobial infection include opened-fracture (odds ratio, 2.223), hypoproteinemia (odds ratio, 2.328), and multiple fractures (odds ratio, 1.465). It is important to note that the antibiotics resistance and sensitivity analysis of the pathogens may be influenced by complications or comorbidities. CONCLUSIONS: This study provides the latest data of PTRLO in China and offers trustworthy guidelines for clinical practice. (China Clinical Trials.gov number, ChiCTR1800017597).

Safety of Prepping the External Fixator In Situ During Staged Internal Fixation of Pilon Fractures: A Retrospective Comparative Cohort Study.

OBJECTIVE: (1) To assess the rate of fracture-related infection (FRI) and unplanned reoperation of disinfecting and prepping in the external fixator (Ex-Fix) instrument during definitive open reduction and internal fixation (ORIF) of pilon fractures treated by a staged protocol and (2) to determine whether the amount of time from external fixation to ORIF influences the risk of FRI. DESIGN: Retrospective cohort study. SETTING: Level 1 academic trauma center. PATIENTS: One hundred thirty-three patients who underwent operative treatment for pilon fracture between 2010 and 2020. INTERVENTION: External fixation and ORIF with or without the Ex-Fix prepped in situ during definitive fixation. MAIN OUTCOME MEASUREMENTS: FRI and unplanned reoperation rates. RESULTS: 133 patients were enrolled, of which 47 (35.3%) had Ex-Fix elements prepped in situ. There was an overall infection rate of 23.3% and unplanned reoperation rate of 11.3%, and there was no significant difference in rates between the 2 cohorts. Patients with Ex-Fix elements prepped in situ who developed an FRI had a higher rate of MRSA and MSSA . Diabetes ( P = 0.0019), open fracture ( P = 0.0014), and longer (≥30 days) interval to ORIF ( P = 0.0001) were associated with postoperative FRI. CONCLUSIONS: Prepping elements of the Ex-Fix in situ did not lead to an increase in rates of FRI or unplanned reoperation. Although diabetes and open fracture were associated with FRI risk, a stronger association was a longer interval of Ex-Fix utilization before definitive internal fixation, specifically 30 days or greater. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Reduced angiogenesis and delayed endochondral ossification in CD163-/- mice highlights a role of M2 macrophages during bone fracture repair.

While recent studies showed that macrophages are critical for bone fracture healing, and lack of M2 macrophages have been implicated in models of delayed union, functional roles for specific M2 receptors have yet to be defined. Moreover, the M2 scavenger receptor CD163 has been identified as a target to inhibit sepsis following implant-associated osteomyelitis, but potential adverse effects on bone healing during blockage therapy have yet to be explored. Thus, we investigated fracture healing in C57BL/6 versus CD163-/- mice using a well-established closed, stabilized, mid-diaphyseal femur fracture model. While gross fracture healing in CD163-/- mice was similar to that of C57BL/6, plain radiographs revealed persistent fracture gaps in the mutant mice on Day 14, which resolved by Day 21. Consistently, 3D vascular micro-CT demonstrated delayed union on Day 21, with reduced bone volume (74%, 61%, and 49%) and vasculature (40%, 40%, and 18%) compared to C57BL/6 on Days 10, 14, and 21 postfracture, respectively (p < 0.01). Histology confirmed large amounts of persistent cartilage in CD163-/- versus C57BL/6 fracture callus on Days 7 and 10 that resolves over time, and immunohistochemistry demonstrated deficiencies in CD206+ M2 macrophages. Torsion testing of the fractures confirmed the delayed early union in CD163-/- femurs, which display decreased yield torque on Day 21, and a decreased rigidity with a commensurate increase in rotation at yield on Day 28 (p < 0.01). Collectively, these results demonstrate that CD163 is required for normal angiogenesis, callus formation, and bone remodeling during fracture healing, and raise potential concerns about CD163 blockade therapy.

Evidence of Neutralizing and Non-Neutralizing Anti-Glucosaminidase Antibodies in Patients With S. Aureus Osteomyelitis and Their Association With Clinical Outcome Following Surgery in a Clinical Pilot.

Staphylococcus aureus osteomyelitis remains a very challenging condition; recent clinical studies have shown infection control rates following surgery/antibiotics to be ~60%. Additionally, prior efforts to produce an effective S. aureus vaccine have failed, in part due to lack of knowledge of protective immunity. Previously, we demonstrated that anti-glucosaminidase (Gmd) antibodies are protective in animal models but found that only 6.7% of culture-confirmed S. aureus osteomyelitis patients in the AO Clinical Priority Program (AO-CPP) Registry had basal serum levels (>10 ng/ml) of anti-Gmd at the time of surgery (baseline). We identified a small subset of patients with high levels of anti-Gmd antibodies and adverse outcomes following surgery, not explained by Ig class switching to non-functional isotypes. Here, we aimed to test the hypothesis that clinical cure following surgery is associated with anti-Gmd neutralizing antibodies in serum. Therefore, we first optimized an in vitro assay that quantifies recombinant Gmd lysis of the M. luteus cell wall and used it to demonstrate the 50% neutralizing concentration (NC50) of a humanized anti-Gmd mAb (TPH-101) to be ~15.6 µg/ml. We also demonstrated that human serum deficient in anti-Gmd antibodies can be complemented by TPH-101 to achieve the same dose-dependent Gmd neutralizing activity as purified TPH-101. Finally, we assessed the anti-Gmd physical titer and neutralizing activity in sera from 11 patients in the AO-CPP Registry, who were characterized into four groups post-hoc. Group 1 patients (n=3) had high anti-Gmd physical and neutralizing titers at baseline that decreased with clinical cure of the infection over time. Group 2 patients (n=3) had undetectable anti-Gmd antibodies throughout the study and adverse outcomes. Group 3 (n=3) had high titers +/- neutralizing anti-Gmd at baseline with adverse outcomes. Group 4 (n=2) had low titers of non-neutralizing anti-Gmd at baseline with delayed high titers and adverse outcomes. Collectively, these findings demonstrate that both neutralizing and non-neutralizing anti-Gmd antibodies exist in S. aureus osteomyelitis patients and that screening for these antibodies could have a value for identifying patients in need of passive immunization prior to surgery. Future prospective studies to test the prognostic value of anti-Gmd antibodies to assess the potential of passive immunization with TPH-101 are warranted.

The fracture liaison service: its history, current state, how it works, and future directions.

Osteoporotic fractures often result in reduced function after healing, with associated pain, disability, loss of independence, and reduced quality of life. Following osteoporotic fractures, it is common for older adults to sustain subsequent, or secondary, fractures. These fractures include those of the proximal femur, vertebrae, distal radius, proximal humerus, and other sites. Although widely recognized as a gap in care, the implementation of appropriate secondary fracture prevention programs has been carried out in most countries. A Fracture Liaison Service represents the best secondary fracture prevention model of care for managing osteoporosis following fragility fractures and falls. These programs have proven to be cost-effective, and represent a major advancement in patient care over those "usual care practices" seen in most community and academic medical centers. Key Fracture Liaison Service programmatic functions include case finding, patient assessment, osteoporosis assessment, initiation of osteoporosis treatment, falls prevention, education, and exercise.

Systemic IL-27 administration prevents abscess formation and osteolysis via local neutrophil recruitment and activation.

Interleukin-27 is a pleiotropic cytokine whose functions during bacterial infections remain controversial, and its role in patients with S. aureus osteomyelitis is unknown. To address this knowledge gap, we completed a clinical study and observed elevated serum IL-27 levels (20-fold higher, P < 0.05) in patients compared with healthy controls. Remarkably, IL-27 serum levels were 60-fold higher in patients immediately following septic death than in uninfected patients (P < 0.05), suggesting a pathogenic role of IL-27. To test this hypothesis, we evaluated S. aureus osteomyelitis in WT and IL-27Rα-/- mice with and without exogenous IL-27 induction by intramuscular injection of rAAV-IL-27p28 or rAAV-GFP, respectively. We found that IL-27 was induced at the surgical site within 1 day of S. aureus infection of bone and was expressed by M0, M1 and M2 macrophages and osteoblasts but not by osteoclasts. Unexpectedly, exogenous IL-27p28 (~2 ng·mL-1 in serum) delivery ameliorated soft tissue abscesses and peri-implant bone loss during infection, accompanied by enhanced local IL-27 expression, significant accumulation of RORγt+ neutrophils at the infection site, a decrease in RANK+ cells, and compromised osteoclast formation. These effects were not observed in IL-27Rα-/- mice compared with WT mice, suggesting that IL-27 is dispensable for immunity but mediates redundant immune and bone cell functions during infection. In vitro studies and bulk RNA-seq of infected tibiae showed that IL-27 increased nos1, nos2, il17a, il17f, and rorc expression but did not directly stimulate chemotaxis. Collectively, these results identify a novel phenomenon of IL-27 expression by osteoblasts immediately following S. aureus infection of bone and suggest a protective role of systemic IL-27 in osteomyelitis.

Significant Reduction in Short-Term Complications Following Unicompartmental Versus Total Knee Arthroplasty: A Propensity Score Matched Analysis.

BACKGROUND: Total knee arthroplasty (TKA) is a gold standard surgical treatment for end-stage arthritis and unicompartmental knee arthroplasty (UKA) is an alternative for localized disease in appropriate patients. Both have been shown to have equivalent complications in the short-term period. We aimed to explore the differences in 30-day complication rates between UKA and TKA using recent data. METHODS: Current Procedural Terminology codes identified patients in the American College of Surgeons National Surgical Quality Improvement Program database who underwent primary TKA or UKA from 2014 to 2018. Propensity score matching addressed demographic differences. Rate of any adverse event (AAE) and complications were compared. RESULTS: We identified 279,852 patients with 270,786 and 9,066 undergoing TKA and UKA. No significant difference was observed in baseline demographics after matching. The AAE rate differed significantly between TKA (5.07%) and UKA (2.38%) cohorts (P < .001). TKA group experienced more wound dehiscence, cerebrovascular accident, postoperative blood transfusion, deep vein thrombosis, and requirement for postoperative intubation. Rate of extended length of stay differed between the TKA (11.35%) and UKA (4.89%) cohorts (P < .001). Accounting for all other variables, preoperative corticosteroid use, bleeding disorder, and chronic obstructive pulmonary disease increased the risk for AAE for both groups. Increasing American Society of Anesthesiologists class also increased the odds for complication proportionally with increasing age and operative time. CONCLUSION: Contrary to previous data, we found a significantly higher 30-day complication rate in TKA patients. TKA patients had a higher likelihood of having an extended length of stay. Multivariable analysis identified preoperative steroid use, bleeding disorder, and chronic obstructive pulmonary disease as risk factors for developing adverse events for both groups. LEVEL OF EVIDENCE: Level III.

Low albumin level is more strongly associated with adverse outcomes and Staphylococcus aureus infection than hemoglobin A1C or smoking tobacco.

Postsurgical deep musculoskeletal infections are a major clinical problem in Orthopaedic Surgery. A serum-based nomogram, which can objectively risk-stratify patients, and aid surgeons in delineating infection risk associated with orthopedic surgical interventions, would be immensely helpful. Here, we constructed a multi-parametric nomogram based on serum anti-Staphylococcus aureus antibody responses, patient characteristics including demographics and standard clinical tests. This nomogram was formally tested in a prospective cohort study comparing 303 hospitalized patients with culture-confirmed S. aureus infection compared with a cohort of 223 healthy screened preoperative patients. Serum anti-S. aureus antibody responses, standard of care clinical tests, and patient demographic data were utilized to perform multivariate logistic regression analysis to quantify the presence of infection and adverse outcome using odds ratios (OR) and to assess predictive ability via area under the ROC curve (AUC). At enrollment, high anti-S. aureus IgG titers were predictive of infection. Remarkably, low serum albumin was found to be significantly associated with infection (OR = 479.963, 95% CI 61.59 - 3740.33, p < 0.0001) and this finding was surprisingly higher than BMI or HbA1c-associations. Combining all risk factors in the nomogram yielded a diagnostic AUC of 0.949 for predicting S. aureus infection. Our results indicate that a serum-based multi-parametric nomogram can be useful in diagnosing S. aureus infections, and importantly, malnourishment is significantly associated with these infections.

Risk Factors for Infection and Subsequent Adverse Clinical Results in the Setting of Operatively Treated Pilon Fractures.

OBJECTIVE: To determine patient-specific and injury-specific factors that may predict infection and other adverse clinical results in the setting of tibial pilon fractures. DESIGN: Retrospective chart review. SETTING: Level 1 academic trauma center. PATIENTS: Two hundred forty-eight patients who underwent operative treatment for tibial pilon fractures between 2010 and 2020. INTERVENTION: External fixation and/or open reduction and internal fixation. MAIN OUTCOME MEASUREMENTS: Fracture-related infection rates and specific bacteriology, risk factors associated with development of a fracture-related infection, and predictors of adverse clinical results. RESULTS: Two hundred forty-eight patients were enrolled. There was an infection rate of 21%. The 3 most common pathogens cultured were methicillin-resistant Staphylococcus aureus (20.3%), Enterobacter cloacae (16.7%), and methicillin-resistant Staphylococcus aureus (15.5%). There was no significant difference in age, sex, race, body mass index, or smoking status between those who developed an infection and those who did not. Patients with diabetes mellitus ( P = 0.0001), open fractures ( P = 0.0043), and comminuted fractures (OTA/AO 43C2 and 43C3) ( P = 0.0065) were more likely to develop a fracture-related infection. The presence of a polymicrobial infection was positively associated with adverse clinical results ( P = 0.006). History of diabetes was also positively associated with adverse results ( P = 0.019). CONCLUSIONS: History of diabetes and severe fractures, such as those that were open or comminuted fractures, were positively associated with developing a fracture-related infection after the operative fixation of tibial pilon fractures. History of diabetes and presence of a polymicrobial infection were independently associated with adverse clinical results. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Rationale and process for N95 respirator sanitation and reuse in the coronavirus disease 2019 (COVID-19) pandemic.

OBJECTIVE: The novel severe acute respiratory coronavirus virus 2 (SARS-CoV-2) was first reported in Wuhan, China, in December 2019 and is notable for being highly contagious and potentially lethal; and SARS-CoV-2 is mainly spread by droplet transmission. The US healthcare system's response to the COVID-19 pandemic has been challenged by a shortage of personal protective equipment (PPE), especially N95 respirators. Restricted use, reuse, and sanitation of PPE have been widely adopted to provide protection for frontline healthcare workers caring for often critically ill and highly contagious patients. Here, we describe our validated process for N95 respirator sanitation. DESIGN: Process development, validation, and implementation. SETTING: Level 1, urban, academic, medical center. METHODS: A multidisciplinary team developed a novel evidence-based process for N95 respirator reprocessing and sanitation using ultraviolet (UV) light. Dose measurement, structural integrity, moisture content, particle filtration, fit testing, and environmental testing were performed for both quality control and validation of the process. RESULTS: The process achieved UV light dosing for sanitation while maintaining the functional and structural integrity of the N95 respirators, with a daily potential throughput capacity of ∼12,000 masks. This process has supported our health system to provide respiratory PPE to all frontline team members. CONCLUSIONS: This novel method of N95 respirator sanitation can safely enable reuse of the N95 respirators essential for healthcare workers caring for patients with COVID-19. Our high-throughput process can extend local supplies of this critical PPE until the national supply is replenished.

Variation in practice for preoperative antibiotic prophylaxis: a survey from an academic tertiary referral center in the United States.

BACKGROUND: Antibiotic surgical prophylaxis is a core strategy for prevention of surgical site infections (SSI). Despite best practice guidelines and known efficacy of antibiotic prophylaxis in decreasing SSI risk, there is often wide variation in its use. This study was designed to determine the individual perspectives of perioperative providers at an academic tertiary referral center regarding their knowledge of preoperative antibiotic choice, dosing, and timing. METHODS: A prospective survey was conducted amongst surgical and anesthesia team members involved in preoperative antibiotic decision making. The survey addressed ten key principles relating to preoperative antibiotic use, including antibiotic choice, timing and rate of infusion, and dosing. The survey was distributed among orthopaedic surgeons, residents, and anesthesia providers at their respective monthly service line meetings between August 2017 to June 2019. The data was stored and analyzed in a Microsoft Excel worksheet. RESULTS: A total of 73 providers completed the survey. Twenty-two (30 %) of the providers agreed and 47 (64 %) disagreed that both vancomycin and cefazolin are equally effective for antibiotic prophylaxis. As for antibiotic choice in patients with penicillin allergies, 37 (51 %) agreed with vancomycin, 21 (29 %) agreed with clindamycin, and 15 (21 %) disagreed with both alternatives. When providers were surveyed regarding the appropriateness of standard versus weight adjusted dosing, 67 (92 %) agreed that vancomycin should be weight adjusted and 63 (86 %) agreed that cefazolin should be weight adjusted. CONCLUSIONS: There is no clear consensus amongst providers for which antibiotic to administer for antibiotic prophylaxis despite existing guidelines. Discrepancy also exists between orthopaedic surgery and anesthesia providers in regards to appropriate antibiotic choice for patients with reported penicillin allergies. Institutions should implement evidence-based protocols for preoperative antibiotic prophylaxis and continue to prospectively monitor compliance in order to identify any inconsistencies that could result in inappropriate antibiotic prophylaxis for patients.

Barriers and Resources to Optimize Bone Health in Orthopaedic Education: Own the Bone (OTB): Bone Health Education in Residency.

Osteoporosis is a critical public health issue with substantial morbidity and healthcare costs. Resident education on osteoporosis is not standardized. Little is known about the barriers to osteoporosis treatment and the usefulness of educational programming from the perspective of orthopaedic residency program directors (PDs). METHODS: This study aims to evaluate the current state and perception of bone health education from the perspective of orthopaedic residency PDs. Therefore, a self-designed 29-question online survey was sent to 129 PDs in the United States to assess bone health education. The information, collected from August to October 2020, included program characteristics, participation in the American Orthopaedic Association's Own the Bone (AOA/OTB) program or any fracture liaison service (FLS) program, availability of faculty, potential barriers, and educational resources. Data collection was performed anonymously with a 47% response rate. RESULTS: The results were compared between programs that used the AOA/OTB program (30%) or any FLS program (28%) (58% OTB or any FLS) vs. programs that did not have any program (42%). Subsequent subanalysis was performed comparing AOA/OTB vs. any FLS vs. no program. Programs that did not have any FLS were least likely to have a formal education syllabus (p = 0.01). When comparing clinical education of residents on bone health, 64% of programs without any system did not provide any formal clinical exposure such as a bone health clinic vs. assessment in patients with fracture compared with 24% of OTB programs and 44% of programs with any FLS (p = 0.02). When asked about desired resources, 47% would find a bone health rotation useful. Among all PDs, 60% support the concept of a 5-year AOA Council of Orthopaedic Residency Directors (CORD)/OTB osteoporosis curriculum. DISCUSSION: The key findings were that institutions including OTB or any FLS in their programs had better availability of specialty consultants, faculty, and a FLS coordinator.