The role of computed tomography in the detection of traumatic arthrotomies of the elbow: a cadaveric study.

Purpose: To evaluate the use of computed tomography (CT) imaging as a diagnostic tool for elbow arthrotomies using a standardized cadaveric arthrotomy model. Method: Nineteen intact fresh frozen cadaver elbows were CT scanned using 2 mm cuts with sagittal and coronal reformats in the plane of the joint and used as controls. An elbow arthrotomy at the posterocentral arthroscopic portal site was performed in all specimens using a 4.5 millimeter trocar. After arthrotomy, all elbows underwent a second CT scan followed by a standard saline load test (SLT). Images were randomized and reviewed by 2 blinded, independent reviewers. Bimodal scoring was performed for each specimen with regard to the presence of an arthrotomy indicated by presence of air in the joint. Regarding the SLT, saline exiting the arthrotomy wound was considered a positive test. Results: CT scans were found to have 100% sensitivity and 86% specificity for diagnosing elbow arthrotomies. Interrater reliability calculated with Cohen kappa statistic was near perfect at r = 0.89. The SLT had a sensitivity of 79% when 20 mL was injected. A total of 25 mL of saline was required to be injected for a sensitivity greater than 95%. Conclusion: This study demonstrates that CT scan is a reliable and less technically demanding method of diagnosis arthrotomies with high interrater reliability and high sensitivity and with results comparable with SLT. This technique may be useful in centers where trained providers are not readily available to perform SLT. Clinical study is required to validate our results. Level of Evidence: Level II.

Stabilization of Vancouver B Periprosthetic Femur Fractures With Cerclage Wiring: A Retrospective Chart Review.

BACKGROUND: While biomechanical and clinical studies detailing the equivalence and, sometimes, the superiority of cerclage wiring fixation compared to plate fixation in select fractures (Vancouver B1 and C) exist, no studies exist detailing outcomes after cerclage wiring fixation in all Vancouver B fracture types. This study explores whether there is a difference in clinical outcomes between Vancouver B fractures fixed with cerclage wiring and those without. METHODS: This retrospective multicenter study reviewed 295 patients from 2007 to 2018 with periprosthetic femur fractures. Vancouver B periprosthetic fractures stabilized utilizing cerclage wiring were identified and compared against fractures stabilized without cerclage wiring, with 33% being B1, 48.4% B2, and 18.6% B3 fractures. Demographics, injury details, fracture classification, surgical details, fracture union, and postoperative complications were recorded for each patient. RESULTS: A majority of our patients were females (65.9%) and were older than 71 years of age (65.6%) without diabetes (63.3%) or smoking history (92.2%). Sixty-nine patients progressed to fracture union (76.7%), two (2.2%) to delayed union, and 19 (21.1%) to nonunion. There was no difference in the union rate (p = 0.98) or time to union (p = 0.91) between the fixation methods. Finally, there was no difference in the infection rate (p = 0.81), re-fracture rate (p = 0.87), or re-operation rate (p = 0.75) between the fixation methods. CONCLUSION: Periprosthetic femur fractures are common injuries, most commonly occurring after low-energy mechanisms in the elderly female population. While the Vancouver fracture pattern helps to guide the surgical construct used for fixation, the use of cerclage wires does not impact bony union in these injuries. Interestingly, increasing age and female gender were associated with increased union rates. Surgeons should individually consider each patient's demographic as well as fracture type when deciding which construct will achieve stable fixation that allows for fracture healing.

Factors Influencing Geriatric Orthopaedic Trauma Mortality.

INTRODUCTION: This study aimed to: (1) evaluate the independent risk factors related to survival and mortality and (2) predict survival in geriatric orthopaedic trauma patients admitted to our institution's ICU as a Level 1 or 2 trauma activation. METHODS: A retrospective review was performed on patients age >60, over a 10 year period, who were involved in a multi-trauma with orthopaedic injuries. Variables evaluated include: sex, age, Injury Severity Score (ISS), mechanism of injury, number and type of orthopaedic injury, anticoagulant use, comorbidities, length of stay in intensive care unit (ICU), type of ICU, ventilator use, vasopressors use, incidence of multiple organ dysfunction syndrome (MODS), number of surgeries, and 1-month and 6-month mortality. A Kaplan-Meier estimator and Cox proportional hazards analysis were used to predict and assess survival probability. RESULTS: 174 patients were included, with an average mortality of 47.7%. Deceased patients had a significantly greater age, ISS, vasopressor usage, ICU stay, incidence of MODF, incidence of genitourinary disease, anticoagulant usage, ventilator usage, number of orthopaedic surgeries, and orthopaedic injuries. The relative risk for mortality within the first month was significantly associated with increased age, ISS, high-energy trauma, length of ICU stay, MODS, psychiatric disease, and anticoagulant use. Patients with an ISS ≤30 were significantly more likely to survive than patients with an ISS of >30. Greater age, ISS, length of ICU stay, incidence of MODS, anticoagulant, and ventilator use were significantly predictive of lower survival rates. Mechanism of injury, number of orthopaedic surgeries and orthopaedic injuries, and type of orthopaedic injury were not found to be predictive of survival. CONCLUSIONS: An ISS >30 at admission is strongly predictive of a lower probability of survival. Genitourinary disease was associated with increased mortality. Low age, ISS, length of stay in ICU, incidence of MODS, anticoagulant use, and ventilator use, are significantly predictive of survival. Number of orthopaedic surgeries, orthopaedic injuries, and type of orthopaedic injury were not found to be predictive of survival. These indications help us to better understand factors predictive of death among geriatric orthopaedic trauma patients, and improve the way we can diagnose and care for them.

Descriptive Analysis of Orthopaedic Surgery Residency Program Directors.

The purpose of this study was to analyze the demographics and backgrounds of U.S. orthopaedic surgery residency program directors (PDs). We collected publicly available information on 189 orthopaedic surgery residency PDs. Of those PDs, 90% were male MDs with an average age of 52. The average age at PD appointment was 45. The average duration of appointment was 7 years. About 81% of programs were university-affiliated, and 61% were in an urban environment. PDs attended 100 medical schools, 129 residencies, and 96 fellowships. of PDs, 87% completed fellowships, commonly in trauma and sports medicine. There was no significant difference between male and female PDs when comparing age, academic appointment, or urban/rural environment. Most female PDs (89%) were at university-based hospitals. Of PDs at osteopathic-focused programs, 28% had an MD/PD. No program with an allopathic focus had a DO/PD. Lastly, 38% of PDs worked at the center where they completed residency. (Journal of Surgical Orthopaedic Advances 31(4):252-255, 2022).

Union rate, complication rate, and opioid usage after Vancouver B periprosthetic femur fractures: a comparison of fracture types.

INTRODUCTION: Periprosthetic femur fractures are complex injuries that can be difficult to treat and recover from. With a growing number of total hip arthroplasties (THA) and revision arthroplasties being performed in an aging population, the incidence of these injuries is on the rise. Multiple studies exist detailing outcomes associated with periprosthetic femur fractures after THA, but no study has directly compared the post-operative course between fracture types as classified by the Vancouver classification system. This study compares the three Vancouver B fracture types to see if any type is associated with an increase in post-operative complications than others. MATERIALS AND METHODS: This retrospective chart review was conducted at a suburban orthopedic surgery department. Overall, 122 patients who presented to our hospital with periprosthetic proximal femur fractures after hip arthroplasty over the past 13 years were reviewed. Patients were included if they underwent surgical stabilization of their femur fracture. Patients were excluded if they underwent non-operative treatment or had missing chart information. For each patient, demographic information, fracture information, surgical information, post-operative course, and post-operative opioid usage were recorded and compared among groups. RESULTS: Overall, 88 fractures were included. Fifty-five (62.5%) were Vancouver type B1, 27 (30.7%) were Vancouver type B2, and 6 (6.8%) were Vancouver type B3. Most of our patients were female (n = 62, 70.5%) and older than 81 years of age (n = 53, 60.2%) with uncemented prosthesis (n = 83, 94.3%). All three fracture groups had statistically similar union rates (p = 0.77), infection rates (p = 0.32), subsequent fractures (p = 0.63), repeat surgeries (p = 0.64), and post-operative opioid use (measured in milli-morphine equivalents) after surgical stabilization (p = 0.96). CONCLUSIONS: While periprosthetic femur fractures after hip arthroplasty are associated with high complication rates and poor outcomes, there is no difference in union rate, infection rate, subsequent fractures, repeat surgery rate, and opioid usage between the different Vancouver B fracture types. LEVEL OF EVIDENCE: Prognostic level III.

What is the Real Rate of Radial Nerve Injury After Humeral Nonunion Surgery?

OBJECTIVES: To determine the radial nerve palsy (RNP) rate and predictors of injury after humeral nonunion repair in a large multicenter sample. DESIGN: Consecutive retrospective cohort review. SETTING: Eighteen academic orthopedic trauma centers. PATIENTS/PARTICIPANTS: Three hundred seventy-nine adult patients who underwent humeral shaft nonunion repair. Exclusion criteria were pathologic fracture and complete motor RNP before nonunion surgery. INTERVENTION: Humeral shaft nonunion repair and assessment of postoperative radial nerve function. MAIN OUTCOME: Measurements: Demographics, nonunion characteristics, preoperative and postoperative radial nerve function and recovery. RESULTS: Twenty-six (6.9%) of 379 patients (151 M, 228 F, ages 18-93 years) had worse radial nerve function after nonunion repair. This did not differ by surgical approach. Only location in the middle third of the humerus correlated with RNP (P = 0.02). A total of 15.8% of patients with iatrogenic nerve injury followed for a minimum of 12 months did not resolve. For those who recovered, resolution averaged 5.4 months. On average, partial/complete palsies resolved at 2.6 and 6.5 months, respectively. Sixty-one percent (20/33) of patients who presented with nerve injury before their nonunion surgery resolved. CONCLUSION: In a large series of patients treated operatively for humeral shaft nonunion, the RNP rate was 6.9%. Among patients with postoperative iatrogenic RNP, the rate of persistent RNP was 15.8%. This finding is more generalizable than previous reports. Midshaft fractures were associated with palsy, while surgical approach was not. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

A Multidisciplinary Approach to Expedite Surgical Hip Fracture Care.

INTRODUCTION: In 2014, we implemented a geriatric hip fracture patient care pathway at our institution which was designed to improve outcomes and decrease time to surgery. MATERIALS AND METHODS: We analyzed retrospective data from 463 patients, aged greater than 50, who had surgical treatment for a closed hip fracture due to a low-energy injury between 2013 and 2016 at an academic institution. Objective outcome measures included time to surgery, mortality rate, and total hospital length of stay. Our primary goal was to decrease the time to surgery for definitive fracture fixation to within 24 hours of admission to the hospital for patients who were medically fit for surgery. RESULTS: We implemented a multidisciplinary, collaborative approach to address the needs of this specific patient population. Prior to implementing the pathway in 2013, our baseline time to surgery within 24 hours was 74.67%. After implementation, we had incremental yearly increases in the percentage of patients operated on within 24 hours, 82.31% in 2014 (P = .10) and 84.14% in 2015 (P = .04). During the study period, our overall time to surgery was reduced by 27% with an initial average of 20.22 hours in 2013, decreasing to 15.33 hours in 2014, and 14.63 hours in 2015. Our mortality rate at 1 year was 16% in 2013, 17% in 2014, and 15% in 2015. CONCLUSION: With implementation of the pathway, we were able to expedite surgical care for our patients and demonstrate a 10% improvement in the percentage of patients able to have surgery within 24 hours over a 3-year period. Our mortality and hospital length of stay, however, remained the same. Through this collaborative process and system standardization, we believe we have significantly improved not only direct patient care but their overall hospital experience. We continue to make improvements in our pathway.

Antibiotic Prophylaxis in Open Fractures: Evidence, Evolving Issues, and Recommendations.

Open fractures are often associated with high-energy trauma and have an increased risk of infection because of surrounding soft-tissue damage and the introduction of environmental contaminants that may communicate with the fracture site. The Gustilo-Anderson classification of open fractures has been used to guide prophylactic antibiotic therapy because different types of open fracture have been shown to have varying rates of surgical site infections with different combinations of pathogens. Prophylactic treatment with various classes of antibiotics, including penicillins and cephalosporins, aminoglycosides, and fluoroquinolones, has evolved over the past half century. More recently, broader spectrum agents including monobactams and glycopeptides have been used for additional coverage. Duration of antibiotic therapy remains variable between institutions, and antibiotic choice is not standardized. Coverage for nosocomial and multidrug-resistant organisms is an ongoing area of clinical research.

Periodic Coulomb Tree Method: An Alternative to Parallel Particle Mesh Ewald.

Particle mesh Ewald (PME) is generally the method of choice for handling electrostatics in simulations with periodic boundary conditions. The excellent efficiency of PME on low processor counts is largely due to the use of the fast Fourier transform (FFT). However, due to the FFT's high communication cost, PME scales poorly in parallel. We develop a periodic Coulomb tree (PCT) method for electrostatic interactions in periodic boundary conditions as an alternative to PME in parallel simulations. We verify the accuracy of PCT by comparison of structural and dynamical properties of three different systems obtained via MD simulations using PME and PCT and provide parallel timing comparisons of the two methods on up to 1024 cores.

Advanced Potential Energy Surfaces for Molecular Simulation.

Advanced potential energy surfaces are defined as theoretical models that explicitly include many-body effects that transcend the standard fixed-charge, pairwise-additive paradigm typically used in molecular simulation. However, several factors relating to their software implementation have precluded their widespread use in condensed-phase simulations: the computational cost of the theoretical models, a paucity of approximate models and algorithmic improvements that can ameliorate their cost, underdeveloped interfaces and limited dissemination in computational code bases that are widely used in the computational chemistry community, and software implementations that have not kept pace with modern high-performance computing (HPC) architectures, such as multicore CPUs and modern graphics processing units (GPUs). In this Feature Article we review recent progress made in these areas, including well-defined polarization approximations and new multipole electrostatic formulations, novel methods for solving the mutual polarization equations and increasing the MD time step, combining linear-scaling electronic structure methods with new QM/MM methods that account for mutual polarization between the two regions, and the greatly improved software deployment of these models and methods onto GPU and CPU hardware platforms. We have now approached an era where multipole-based polarizable force fields can be routinely used to obtain computational results comparable to state-of-the-art density functional theory while reaching sampling statistics that are acceptable when compared to that obtained from simpler fixed partial charge force fields.

Percutaneous Sacroiliac Screw Technique.

Remembering that preoperative planning, surgical indications, and fracture reduction are paramount for this procedure, presented here is our technique for performing percutaneous sacroiliac screws, both transiliac-transsacral and sacral style. A combination of video, still pictures, and fluoroscopy images will guide the viewer through the process we routinely use highlighting specific details. Patient positioning and intraoperative fluoroscopy imaging are critical to a successful procedure. Although inlet and outlet films remain important, we find the procedure best started on the lateral sacral view to reduce the need for start site, trajectory, and imaging position changes during the case. A cannulated pig sticker (drill guide) used with long drill tip guide wires provide improved manual control to both finding a good start site and directing the trajectory. For patient safety, sacral anatomy and safe zones are discussed as well. Using these technical points will help make this a successful procedure.

Development of Clostridium septicum gas gangrene as an adverse effect of clindamycin-induced Clostridium difficile infection in a pediatric patient.

Clostridium myonecrosis or gas gangrene is a life-threatening infection characterized by either traumatic or atraumatic etiology. It has been widely described in patients with traumatic open wounds and in immunocompromised patients, including malignancy. A third source can result from natural flora in the gastrointestinal tract after bowel ischemia. This is a rare occurrence and is even less commonly described in the pediatric population. We present a pediatric patient who developed Clostridium septicum myonecrosis as an iatrogenic complication from clindamycin-induced Clostridium difficile ischemic colitis.

Are bilateral femoral fractures no longer a marker for death?

OBJECTIVES: To determine whether previously reported high mortality rates associated with bilateral femoral fractures have decreased over time. DESIGN: Retrospective review. SETTING: Urban academic trauma center. STUDY GROUP: 54 adults with bilateral femoral fractures treated at our center from 2000 to 2006. The 108 fractures were initially treated with external fixation (11%), reamed antegrade nailing (23%), and reamed retrograde nailing (67%). Unilateral control group: 461 patients with unilateral femoral fractures treated at our center from 2002 to 2005. INTERVENTION: Univariate analysis compared our results with those of a published historical control group from the same center approximately 15 years ago (study period, 1984-1990). MAIN OUTCOME MEASUREMENTS: Mortality rates. RESULTS: We noted marked differences between the current mortality rate associated with bilateral femoral fractures and that of the historical control group. The mortality rate decreased over time at our center for both bilateral (26%-7%, P = 0.002) and unilateral (12%-2%, P = 0.0001) fractures. Mortality rates were still significantly higher (P = 0.037) for bilateral (7%) than for unilateral (2%) fractures. CONCLUSIONS: Mortality rates and Injury Severity Scores were reduced for bilateral and unilateral femoral fractures compared with data reported 15 years ago from the same center. The improved outcome might be related in part to changes in resuscitation, triage, intensive care, and orthopaedic management of the patients. However, considering that the Injury Severity Score also significantly decreased, the improvement might have occurred because of changes in injury patterns, perhaps secondary to improved safety features in motor vehicles. LEVEL OF EVIDENCE: Prognostic level III. See instructions for authors for a complete description of levels of evidence.

Comparison of treecodes for computing electrostatic potentials in charged particle systems with disjoint targets and sources.

In molecular simulations, it is sometimes necessary to compute the electrostatic potential at M target sites due to a disjoint set of N charged source particles. Direct summation requires O(MN) operations, which is prohibitively expensive when M and N are large. Here, we consider two alternative tree-based methods that reduce the cost. The standard particle-cluster treecode partitions the N sources into an octree and applies a far-field approximation, whereas a recently developed cluster-particle treecode instead partitions the M targets into an octree and applies a near-field approximation. We compare the two treecodes with direct summation and document their accuracy, CPU run time, and memory usage. We find that the particle-cluster treecode is faster when N > M, that is, when the sources outnumber the targets, and conversely, the cluster-particle treecode is faster when M > N, that is, when the targets outnumber the sources. Hence, the two treecodes provide useful tools for computing electrostatic potentials in charged particle systems with disjoint targets and sources.