Cold Welding of the Synthes Femoral Neck System Encountered at Conversion to Arthroplasty: A Case Report.

CASE: The Synthes Femoral Neck System (FNS) is a relatively new device available to the market in 2019 designed to reduce complication and revision rates after femoral neck fracture stabilization. We present a 77-year-old man with Parkinson disease and avascular necrosis after femoral neck fracture initially managed with the FNS. Subsequent challenges in device removal occurred because of its propensity for bony integration, plate and locking screw welding, and screw head recess destruction. CONCLUSION: Surgeons must recognize the need for additional available equipment (e.g., burr or broken screw removal set) for successful extraction when FNS removal is required.

Delay of fixation increases 30-day complications and mortality in traumatic pelvic ring injuries.

PURPOSE: While decreased time to fixation in femur fractures improves mortality, it remains unclear if the same relationship exists for pelvic fractures. The National Trauma Data Bank (NTDB) is a data repository for trauma hospitals in the United States (injury characteristics, perioperative data, procedures, 30-day complications), and we used this to investigate early, significant complications after pelvic-ring injuries. METHODS: The NTDB (2015-2016) was queried to capture operative pelvic ring injuries in adult patients with injury severity score (ISS) ≥ 15. Complications included medical and surgical complications, as well as 30-day mortality. Multivariable logistic regression was used to investigate the association between days to procedure and complications after adjusting for demographic characteristics and comorbidities. RESULTS: 2325 patients met inclusion criteria. 532 (23.0%) sustained complications, and 72 (3.2%) died within the first 30 days. The most common complications were deep vein thrombosis (DVT) (5.7%), acute kidney injury (AKI) (4.6%), and unplanned intensive care unit (ICU) admission (4.4%). In a multivariate analysis, days to procedure was independently significantly associated with complications, with an adjusted odds ratio (95% confidence interval) of 1.06 (1.03-1.09, P < 0.001), best interpreted as a 6% increase in the odds of complication or death for each additional day. CONCLUSION: Time to pelvic fixation is a significant and modifiable risk factor for major complications and death. This suggests we should prioritize time to pelvic fixation on trauma patients to minimize mortality and major complications.

Radiographic bladder shift is a harbinger of intraoperative blood loss in acetabular surgical fixation.

PURPOSE: The purpose of this study was to characterize the relationship between a novel radiographic measurement on initial AP pelvis radiograph (termed "bladder shift," BS) to intraoperative blood loss (IBL) during acetabular surgical fixation. METHODS: All adult patients receiving unilateral acetabular fixation (Level 1 academic trauma; 2008-18) were reviewed. AP pelvis radiographs were reviewed for visible bladder outlines and then measured to determine the percentage deformation toward the midline. Hemoglobin & hematocrit data were then used to calculate quantitative blood loss between pre- and post- operative blood counts for data analysis. RESULTS: 371 patients with unilateral traumatic acetabular fractures requiring fixation were reviewed; 99 of these had visible bladder outlines, complete blood count and transfusion data (2008-2018; 66% associated patterns). Median bladder shift (BS) was 13.3%. Every 10% of bladder shift was associated with 123 mL greater IBL. Patients with full bladder shift to midline sustained a median 1.5L IBL (interquartile range [IQR] 0.8 to 1.6). Associated patterns had a threefold greater median BS (associated: 16.5% [15.4 to 45.9] vs. elementary: 5.6% [1.1 to 15.4], p < 0.05) and received intraoperative pRBC twice as frequently (57% vs. 24%, p < 0.01). CONCLUSIONS: Radiographic bladder shift is an easily available visual marker, in patients sustaining acetabular fractures, that may predict intraoperative hemorrhage and need for transfusions.

Risk of Revision and Complications After Total Hip Arthroplasty for Acute Treatment of Acetabular Fracture.

BACKGROUND: Total hip arthroplasty (THA) for the treatment of acute acetabular fractures may be indicated where there is high risk for failure of open reduction and internal fixation. This study aimed to determine risks of revision and rates of major complications of THA for acute acetabular fractures. METHODS: A retrospective review was performed (all-claims data files of a large national database) by querying International Classification of Disease, 10th revision procedure codes for THA within 14 days of acetabular fracture. We identified all-cause revision and surgical complications including dislocations, mechanical failures (loosenings or broken prostheses), infections, as well as medical complications. Demographic data collected included age, sex, obesity, and Charlson Comorbidity Index (CCI). Multivariate analyses evaluated the association of revision and major surgical complications after adjusting for demographic characteristics and comorbidities. We identified 956 THAs for the treatment of acute acetabular fracture from 2015 to 2020. Of all acute acetabular fractures treated with THA, 241 were concomitant with open reduction and internal fixation (ORIF), and 715 were THA-alone. RESULTS: All-cause revision risk was 18.2%, overall major surgical complication rate 26.9%, and medical complication rate was 13.2%. Women were associated with increased risk of revision (adjusted odds ratio (aOR) 1.8; confidence interval (CI) 1.3 to 2.6, P = .001), dislocation (aOR 2.0; CI 1.5 to 3.1, P < .001), mechanical complication (aOR 2.1; CI 1.4 to 3.2, P < .001), and infection (aOR 1.6; CI 1.0 to 2.5, P = .044). CONCLUSION: We noted risk of all-cause revision of 18.2%, overall major surgical complication rate of 26.9%, and overall major medical complication rate of 13.2% for THA as the treatment of acute acetabular fracture. We caution against broad expansion of THA for treatment of acute acetabular fractures. Furthermore, increased risks of revision and complications in women warrant additional investigation into patient and fracture characteristics that may contribute to this finding.

Distribution of Bacterial Species and Resistance Patterns in Surgical Site Infection after Prior Administration of Vancomycin and Tobramycin Intrawound Powdered Antibiotic Prophylaxis.

OBJECTIVE: Evaluate the species distribution and resistance patterns of bacterial pathogens causing surgical site infection (SSI) after operative fracture repair, with and without the use of intrawound powdered antibiotic (IPA) prophylaxis during the index surgery. DESIGN: Retrospective cohort study. SETTING: Academic, level 1 trauma center, 2018-2020. PATIENTS/PARTICIPANTS: Fifty-nine deep SSIs were identified in a sample of 734 patients with 846 fractures (IPA [n = 320], control [n = 526]; open [n = 157], closed fractures [n = 689]) who underwent orthopaedic fracture care. Among SSIs, 28 (48%) patients received IPA prophylaxis and 25 (42%) of the fractures were open. INTERVENTION: Intrawound powdered vancomycin and tobramycin. MAIN OUTCOME MEASUREMENTS: Distribution of bacterial species and resistance patterns causing deep surgical site infections requiring operative debridement. RESULTS: Zero patients developed infections caused by resistant strains of streptococci, enterococci, gram-negative enterics, Pseudomonas , or Cutibacterium species. The only resistant strains isolated were methicillin resistance (19%) and oxacillin-resistant coagulase-negative staphylococci (16%). There was no associated statistical difference in the proportion of bacterial species isolated, their resistance profiles, or rate of polymicrobial infections between the IPA and control group. Most (93%) cases using IPAs included vancomycin and tobramycin powders. There were 59 SSIs; 28 (9%) in the IPA cohort and 31 (6%) in the control cohort ( P = 0.13). CONCLUSION: The use of local antibiotic prophylaxis resulted in no measurable increase in the proportion of infections caused by resistant bacterial pathogens after operative treatment of fractures. However, the small sample size and limited time frame of these preliminary data require continued investigation into their role as an adjunct to SSI prophylaxis. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Role of single-dose intravenous iron therapy for the treatment of anaemia after orthopaedic trauma: protocol for a pilot randomised controlled trial.

INTRODUCTION: Orthopaedic trauma and fracture care commonly cause perioperative anaemia and associated functional iron deficiency due to a systemic inflammatory state. Modern, strict transfusion thresholds leave many patients anaemic; managing this perioperative anaemia is an opportunity to impact outcomes in orthopaedic trauma surgery. The primary outcome of this pilot study is feasibility for a large randomised controlled trial (RCT) to evaluate intravenous iron therapy (IVIT) to improve patient well-being following orthopaedic injury. Measurements will include rate of participant enrolment, screening failure, follow-up, missing data, adverse events and protocol deviation. METHODS AND ANALYSIS: This single-centre, pilot, double-blind RCT investigates the use of IVIT for acute blood loss anaemia in traumatically injured orthopaedic patients. Patients are randomised to receive either a single dose infusion of low-molecular weight iron dextran (1000 mg) or placebo (normal saline) postoperatively during their hospital stay for trauma management. Eligible subjects include adult patients admitted for lower extremity or pelvis operative fracture care with a haemoglobin of 7-11 g/dL within 7 days postoperatively during inpatient care. Exclusion criteria include history of intolerance to intravenous iron supplementation, active haemorrhage requiring ongoing blood product resuscitation, multiple planned procedures, pre-existing haematologic disorders or chronic inflammatory states, iron overload on screening or vulnerable populations. We follow patients for 3 months to measure the effect of iron supplementation on clinical outcomes (resolution of anaemia and functional iron deficiency), patient-reported outcomes (fatigue, physical function, depression and quality of life) and translational measures of immune cell function. ETHICS AND DISSEMINATION: This study has ethics approval (Oregon Health & Science University Institutional Review Board, STUDY00022441). We will disseminate the findings through peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: NCT05292001; ClinicalTrials.gov.

Platelet reactivity and platelet count in women with iron deficiency treated with intravenous iron.

Background: Iron deficiency anemia (IDA) and heavy menstrual bleeding are prevalent, interrelated issues impacting over 300 million premenopausal women worldwide. IDA is generally associated with increased platelet counts; however, the effects of IDA and its correction on platelet function in premenopausal women remain unknown. Objectives: We sought to determine how IDA and intravenous iron affect platelet count and platelet function in premenopausal women. Methods: Hematologic indices were assessed in a multicenter, retrospective cohort of 231 women repleted with intravenous iron. Pre- and postinfusion blood samples were then obtained from a prospective cohort of 13 women to analyze the effect of intravenous iron on hematologic parameters as well as platelet function with flow cytometry and platelet aggregation assays under physiologic shear. Results: Following iron replacement, anemia improved, and mean platelet counts decreased by 26.5 and 16.0 K/mm3 in the retrospective and prospective cohorts, respectively. Replacement reduced baseline platelet surface P-selectin levels while enhancing platelet secretory responses to agonists, including collagen-related peptide and ADP. Platelet adhesion and aggregation on collagen under physiologic shear also significantly increased following repletion. Conclusion: We find that intravenous iron improves anemia while restoring platelet counts and platelet secretory responses in premenopausal women with iron deficiency. Our results suggest that iron deficiency as well as iron replacement can have a range of effects on platelet production and function. Consequently, platelet reactivity profiles should be further examined in women and other groups with IDA where replacement offers a promising means to improve anemia as well as quality of life.

Socioeconomic factors and outcomes from exercise-related sudden cardiac arrest in high school student-athletes in the USA.

OBJECTIVE: Minority student-athletes have a lower survival rate from sudden cardiac arrest (SCA) than non-minority student-athletes. This study examined the relationship between high school indicators of socioeconomic status (SES) and survival in student-athletes with exercise-related SCA. METHODS: High school student-athletes in the USA with exercise-related SCA on school campuses were prospectively identified from 1 July 2014 to 30 June 2018 by the National Center for Catastrophic Sports Injury Research. High school indicators of SES included the following: median household and family income, proportion of students on free/reduced lunch and percent minority students. Resuscitation details included witnessed arrest, presence of an athletic trainer, bystander cardiopulmonary resuscitation and use of an on-site automated external defibrillator (AED). The primary outcome was survival to hospital discharge. Differences in survival were analysed using risk ratios (RR) and univariate general log-binomial regression models. RESULTS: Of 111 cases identified (mean age 15.8 years, 88% male, 49% white non-Hispanic), 75 (68%) survived. Minority student-athletes had a lower survival rate compared with white non-Hispanic student-athletes (51.1% vs 75.9%; RR 0.67, 95% CI 0.49 to 0.92). A non-significant monotonic increase in survival was observed with increasing median household or family income and with decreasing percent minority students or proportion on free/reduced lunch. The survival rate was 83% if an athletic trainer was on-site at the time of SCA and 85% if an on-site AED was used. CONCLUSIONS: Minority student-athletes with exercise-related SCA on high school campuses have lower survival rates than white non-Hispanic athletes, but this difference is not fully explained by SES markers of the school.

Is the Iliac Cortical Density Similarly Positioned in the Developing Pediatric Pelvis?

OBJECTIVES: The iliac cortical density (ICD) is a critical fluoroscopic landmark for pelvic percutaneous screw placement. Our purpose was to evaluate the ICD as a landmark in pediatrics and quantify the diameter of osseous pathways for 3 screw trajectories: iliosacral (IS) at S1 and transiliac-transsacral (TSTI) at S1 and S2. METHODS: Two hundred sixty-seven consecutive pelvic CT scans in children 0-16 years of age were analyzed. ICD and S1 vertebral heights were measured at multiple regions along S1. Their height and corresponding ratios, as well as osseous screw corridor dimensions were compared between age groups and by the dysmorphic status. RESULTS: In the nondysmorphic pelvises, S1 height, ICD height, and the ICD to S1 height ratio increased across age groups for all locations (P < 0.001). All 3 screw pathway diameters increased with age (P < 0.001). In the dysmorphic group, there was no increase in ICD to S1 height ratio with age. Except for the age 0-2 group, the ICD to S1 height ratios were significantly larger in the nondysmorphic group. In the dysmorphic group, S1 TSTI pathway remained narrow with age, whereas IS at S1 and TSTI at S2 had a significant increased diameter with age (P < 0.001). CONCLUSION: The ICD is a useful fluoroscopic landmark for percutaneous screw placement in the pediatric pelvis. For nondysmorphic pelvises, the ICD to S1 height ratio, as well as osseous corridors for IS, TSTI at S1, and TSTI at S2 screw trajectories increase significantly with age. The margin for safe screw placement in S1 is smaller for younger and dysmorphic pelvises.

Aetiology and incidence of sudden cardiac arrest and death in young competitive athletes in the USA: a 4-year prospective study.

OBJECTIVE: To investigate the aetiology and incidence of sudden cardiac arrest and death (SCA/D) in US competitive athletes. METHODS: Prospective surveillance was conducted from 1 July 2014 to 30 June 2018 through the National Center for Catastrophic Sports Injury Research in collaboration with national sports organisations. Autopsy reports, death certificates, and medical records were reviewed by an expert panel to determine aetiology. Athlete participation statistics from the National Federation of State High School Associations and the National Collegiate Athletic Association (NCAA) were used to calculate incidence rates per athlete-years (AY). Comparisons of incidence rates were calculated using incidence rate ratios (IRR) with 95% CIs. RESULTS: 331 cases of confirmed SCA/D (158 survivors; 173 fatalities) were identified; 15.4% in middle school, 61.6% in high school and 16.6% in college and professional athletes. Average age was 16.7 (11-29) years, and the majority were in male (83.7%), basketball (28.7%) or American football (25.4%) athletes. Common causes included hypertrophic cardiomyopathy (20.6%), idiopathic left ventricular hypertrophy (13.4%), coronary artery anomalies (12.0%) and autopsy-negative sudden unexplained death (9.6%). Coronary anomalies were more common in middle school athletes (28%), while cardiomyopathies (hypertrophic, arrhythmogenic, dilated, non-compaction or restricted) accounted for 47% of cases in college and professional athletes. Incidence was higher in male versus female athletes at the high school (1:43 932 AY (95% CI 1:38 101 to 1:50 907) vs 1:203 786 AY (95% CI 1:145 251 to 1:293 794); IRR 4.6 (95% CI 3.1 to 7.2)) and NCAA (1:34 906 AY (95% CI 1:25 385 to 1:49 173) vs 1:123 278 AY (95% CI 1:66 078 to 1:249 853); IRR 3.5 (95% CI 1.5 to 9.5)) levels. African American male NCAA Division I basketball players had the highest annual incidence rate of SCA/D (1:2087 AY (95% CI 1:1073 to 1:4 450)). CONCLUSIONS: Cardiomyopathies account for nearly half of SCA/D cases in college and professional athletes, while coronary artery anomalies play a more prominent role than expected in middle school athletes. Over half of SCA cases in athletes result in sudden death, calling for improved prevention strategies.

Etiology of Sudden Cardiac Arrest and Death in US Competitive Athletes: A 2-Year Prospective Surveillance Study.

OBJECTIVE: To determine the etiology of sudden cardiac arrest and death (SCA/D) in competitive athletes through a prospective national surveillance program. DESIGN: Sudden cardiac arrest and death cases in middle school, high school, college, and professional athletes were identified from July 2014 to June 2016 through traditional and social media searches, reporting to the National Center for Catastrophic Sports Injury Research, communication with state and national high school associations, review of the Parent Heart Watch database, and search of student-athlete deaths on the NCAA Resolutions List. Autopsy reports and medical records were reviewed by a multidisciplinary panel to determine the underlying cause. SETTING AND PARTICIPANTS: US competitive athletes with SCA/D. MAIN OUTCOME MEASURES: Etiology of SCA/D. RESULTS: A total of 179 cases of SCA/D were identified (74 arrests with survival, 105 deaths): average age 16.6 years (range 11-29), 149 (83.2%) men, 94 (52.5%) whites, and 54 (30.2%) African American. One hundred seventeen (65.4%) had an adjudicated diagnosis, including 83 deaths and 34 survivors. The most common etiologies included hypertrophic cardiomyopathy (19, 16.2%), coronary artery anomalies (16, 13.7%), idiopathic left ventricular hypertrophy/possible cardiomyopathy (13, 11.1%), autopsy-negative sudden unexplained death (8, 6.8%), Wolff-Parkinson-White (8, 6.8%), and long QT syndrome (7, 6.0%). Hypertrophic cardiomyopathy was more common in male basketball (23.3%), football (25%), and African American athletes (30.3%). An estimated 56.4% of cases would likely demonstrate abnormalities on an electrocardiogram. CONCLUSIONS: The etiology of SCA/D in competitive athletes involves a wide range of clinical disorders. More robust reporting mechanisms, standardized autopsy protocols, and accurate etiology data are needed to better inform prevention strategies.

Survival After Exercise-Related Sudden Cardiac Arrest in Young Athletes: Can We Do Better?

BACKGROUND:: Sudden cardiac arrest (SCA) is the leading cause of death in young athletes during sports. HYPOTHESIS:: Survival after SCA in young athletes is variable. STUDY DESIGN:: Prospective, active surveillance study. LEVEL OF EVIDENCE:: Level 3. METHODS:: From July 1, 2014, to June 30, 2016, exercise-related SCA in competitive young athletes was identified through a systematic search of traditional and social media sources, direct reporting to the National Center for Catastrophic Sports Injury Research, searching of the National Collegiate Athletic Association Resolutions List, regular communication with national and state high school athletic associations, and review of cases in the Parent Heart Watch database. RESULTS:: A total of 132 cases were identified during the 2-year study period (mean patient age, 16 years; age range, 11-27 years; 84% male; 51% white non-Hispanic/Latino, 30% black/African American, and 11% white Hispanic/Latino). High school athletes accounted for 78 (59%) cases, with 28 (21%) in middle school and 15 (11%) in college athletes. Overall survival was 48% (95% CI, 40%-57%; 64 survivors, 68 deaths). Survival was similar in male versus female athletes but higher in white non-Hispanic/Latino (40/67; 60%) versus black/African American (13/39; 33%) athletes (difference, 27%; 95% CI, 7%-45%; P = 0.008) and white non-Hispanic/Latino versus all minority (18/59; 31%) athletes (difference, 29%; 95% CI, 13%-46%; P = 0.001). Basketball accounted for 30% of cases, followed by football (25%), track/cross-country (12%), and soccer (11%). The majority (93%) of cases were witnessed. If a certified athletic trainer was on-site and involved in the resuscitation, 83% of athletes survived. If an on-site automated external defibrillator was used in the resuscitation, 89% of athletes survived. CONCLUSION:: Exercise-related SCA in young, competitive athletes is typically witnessed, providing an opportunity for rapid resuscitation. Additional research is needed to identify factors that affect survival in different athlete populations. CLINICAL RELEVANCE:: Public access defibrillator programs should be universal in schools and youth sporting venues and have the potential to increase survival after SCA in young athletes.

Sodium-dependent phosphate cotransporters and phosphate-induced calcification of vascular smooth muscle cells: redundant roles for PiT-1 and PiT-2.

OBJECTIVE: Elevated serum phosphate has emerged as a major risk factor for vascular calcification. The sodium-dependent phosphate cotransporter, PiT-1, was previously shown to be required for phosphate-induced osteogenic differentiation and calcification of cultured human vascular smooth muscle cells (VSMCs), but its importance in vascular calcification in vivo and the potential role of its homologue, PiT-2, have not been determined. We investigated the in vivo requirement for PiT-1 in vascular calcification using a mouse model of chronic kidney disease and the potential compensatory role of PiT-2 using in vitro knockdown and overexpression strategies. APPROACH AND RESULTS: Mice with targeted deletion of PiT-1 in VSMCs were generated (PiT-1(Δsm)). PiT-1 mRNA levels were undetectable, whereas PiT-2 mRNA levels were increased 2-fold in the vascular aortic media of PiT-1(Δsm) compared with PiT-1(flox/flox) control. When arterial medial calcification was induced in PiT-1(Δsm) and PiT-1(flox/flox) by chronic kidney disease followed by dietary phosphate loading, the degree of aortic calcification was not different between genotypes, suggesting compensation by PiT-2. Consistent with this possibility, VSMCs isolated from PiT-1(Δsm) mice had no PiT-1 mRNA expression, increased PiT-2 mRNA levels, and no difference in sodium-dependent phosphate uptake or phosphate-induced matrix calcification compared with PiT-1(flox/flox) VSMCs. Knockdown of PiT-2 decreased phosphate uptake and phosphate-induced calcification of PiT-1(Δsm) VSMCs. Furthermore, overexpression of PiT-2 restored these parameters in human PiT-1-deficient VSMCs. CONCLUSIONS: PiT-2 can mediate phosphate uptake and calcification of VSMCs in the absence of PiT-1. Mechanistically, PiT-1 and PiT-2 seem to serve redundant roles in phosphate-induced calcification of VSMCs.