Sacroiliac Joint Fusion – Impact of a New Image-Guidance Protocol on Safety and Complications

INTRODUCTION Low back pain is a common affliction impacting patients worldwide. The burden of low back pain on modern society in terms of direct costs associated with diagnosis and treatment, as well as indirect costs such as time missed from work for both patients and caregivers, is estimated to be as high as $100 billion annually in the United States alone.1,2 Up to 2-3% of physician visits are thought to be related to chronic low back pain.1,3 While the traditional focus of healthcare providers has been on lumbosacral pathology, sacroiliac joint dysfunction is an underappreciated and underdiagnosed cause of low back pain. Previous studies3-8 have suggested that 15-30% of chronic low back pain is due to pathology located in the sacroiliac joint. Historically, recognition of this pathology was difficult, limited by lack of standardized diagnostic criteria and disease-specific outcome measures. Traditional treatment focused on conservative therapy, such as physical therapy with focus on core and pelvic stability, orthoses, pain and anti-inflammatory medication, weight loss, intra- or peri-articular injections, and radiofrequency ablation.4,5,9-12 Early surgical intervention came in the form of morbid open approaches often utilizing iliac crest autografting. More recently, minimally invasive techniques for sacroiliac fusion have been developed that allow for significant sparing of muscle dissection, shorter operating room times and blood loss, reduced length of stay, and fewer complications.13-17 Such techniques are often performed with fluoroscopic guidance. However, three-dimensional sacral anatomy can be challenging to conceptualize on fluoroscopic imaging and several centers are now beginning to perform the procedure utilizing image-guidance with intraoperative CT data. This is particularly helpful in patients with transitional lumbosacral anatomy or those undergoing revision procedures. Complications such as pseudarthrosis and neural injuries, while rare, are often associated with need for revision surgery and poorer outcome.18,19 The transition to CT-based image-guidance aims to reduce such complications. The purpose of this study is to review our series of minimally invasive sacroiliac fusion with a focus on safety and complications, and to review differences in these parameters between patients undergoing fluoroscopic technique versus CT-based image-guidance

A Case of Intradural Extramedullary Spinal Tuberculosis Diagnosed 8 Years After Treatment of the Primary Infection

Tuberculosis (TB), the disease caused by Mycobacterium tuberculosis, is the second leading killer worldwide from a single infectious agent. Spinal TB is associated with pulmonary disease and may originate from (1) hematogenous spread outside the central nervous system (CNS), (2) sites located within the cranium (meningitis), or (3) secondary extension from vertebral bodies or discs (Pott’s disease).1 Other presentations of tuberculosis include tuberculous arachnoiditis, nonosseous spinal tuberculoma, and spinal meningitis. Of these conditions, spinal tuberculoma can be intradural, extradural, intramedullary, or extramedullary. Intradural extramedullary tuberculosis is the most rare type and is only observed in 1 out of 50,000 cases of tuberculosis.2,3 To date, there has only been one documented intradural extramedullary tuberculoma in a non-HIV-infected patient in North America.4 Intradural spinal tuberculomas often present simultaneously or are preceded by tuberculous meningitis (TBM).5,6 We treated an otherwise healthy 68-yearold male that developed progressive lower extremity pain and weakness from an intradural spinal tuberculoma. While spinal tuberculomas have been previously described, no prior author has reported a tuberculoma several years after successful eradication of the pulmonary infection. In this case report, we present the case, pertinent imaging, operative findings, histopathology, and a review of the literature

Red Cell Distribution Width: an Unacknowledged Predictor of Mortality and Length of Stay following Revision Arthroplasty

Introduction Red blood cell distribution width (RDW), a measure of variability in size of circulating erythrocytes, is routinely reported in complete blood cell analysis, and together with mean cell volume (MCV) has conventionally been used to distinguish the cause of anemia. It is calculated by (Standard deviation of MCV÷ mean MCV) x 100, with normal range being 11.5%-14.5%. Several recent publications have described RDW as an independent predictor of adverse outcome and mortality in patients with different underlying medical conditions such as acute and chronic heart failure, peripheral artery disease, chronic pulmonary disease and acute kidney injury1. The purposes of this study were 1) to investigate possible relationship between RDW levels and length of stay (LOS) and mortality following revision total joint arthroplasty (TJA), and if that correlation existed, 2) to develop predictive models for LOS and mortality based on preoperative patient-related factors including RDW values

Etiology and Surgical Management of Cervical Spinal Epidural Abscess (SEA):: A Systematic Review.

Study Design: Systematic analysis and review. Objective: Evaluation of the presentation, etiology, management strategies (including both surgical and nonsurgical options), and neurological functional outcomes in patients with cervical spinal epidural abscess (SEA). Methods: The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria were used to create a framework based on which articles pertaining to cervical SEA were chosen for review following a search of the Ovid and PubMed databases using the search terms epidural abscess and cervical. Included studies needed to have at least 4 patients aged 18 years or older, and to have been published within the past 20 years. Results: Database searches yielded 521 potential articles in PubMed and 974 potential articles in Ovid. After review, 11 studies were ultimately identified for inclusion in this systematic review. Surgery appears to be a well-tolerated management strategy with limited complications for patients with cervical SEA. However, the quantity of data comparing medical and surgical treatment of cervical SEA is limited and the bulk of the data is derived from low quality studies. Conclusion: Data reporting was heterogeneous among studies making it difficult to draw discrete conclusions. Early surgical intervention may be appropriate in selected patients with cervical epidural abscess, but it is not clear what distinguishes these patients from those who are successfully managed nonoperatively

Aspirin May Be Adequate for Venous Thromboembolic Event Prophylaxis after Revision Hip and Knee Arthroplasty

Introduction: The optimal prophylaxis for prevention of venous thromboembolic events (VTE) after total hip arthroplasty (THA) and total knee arthroplasty (TKA) remains unknown.(1) Current studies focus on primary arthroplasty and there are little to no data on the ideal prophylaxis for VTE following revision arthroplasty.(2) Revision surgery, due to its complexity, longer operative time, higher risk of bleeding and infection diff­ers from primary arthroplasty.(3) The objective of this study was to evaluate whether aspirin, known to be e­ffective for prevention of VTE after primary arthroplasty, is also e­ffective against such events following revision THA and TKA

Cervical Spine Osteomyelitis after Esophageal Dilation in Patients with a History of Laryngectomy or Pharyngectomy and Pharyngeal Irradiation

Dysphagia is a common sequela of the treatment of head and neck cancer and is frequently managed with esophageal dilation in patients with dysphagia secondary to hypopharyngeal stenosis. Reported complications of esophageal dilation include bleeding, esophageal perforation, and mediastinitis. We examine four cases of cervical spine osteomyelitis presenting as a delayed complication of esophageal dilation for hypopharyngeal stenosis in patients with a history of laryngectomy or pharyngectomy and radiation with or without chemotherapy. The history of head and neck surgery and radiation in these patients further complicates the management of the cervical spine osteomyelitis

Use of practice tracks in the medical specialties.

OBJECTIVES: To evaluate the use of practice tracks by each of the 24 medical specialty boards and to compare this with the experience in emergency medicine (EM). METHODS: Scripted telephone surveys were conducted with representatives of each of the specialty boards. RESULTS: Of 24 specialties currently recognized by the American Board of Medical Specialties (ABMS), 14 (58%) reported a history of a practice track. Eight boards reported never having a practice track and 2 were unsure. All practice tracks have been limited in duration, most commonly closing after a specified period. The mean duration of the practice tracks was 9.8 years, the median was 7.5 years, and the range was 3-27 years. The practice track in EM was open for 9 years. CONCLUSIONS: Practice tracks were common in the early years of most specialties and most were limited by duration. The history of the practice track in EM is not dissimilar to those of other specialties

Operative Environment

Postoperative SSIs are believed to occur via bacterial inoculation at the time of surgery or as a result of bacterial contamination of the wound via open pathways to the deep tissue layers.1–3 The probability of SSI is reflected by interaction of parameters that can be categorized into three major groups.2 The first group consists of factors related to the ability of bacteria to cause infection and include initial inoculation load and genetically determined virulence factors that are required for adherence, reproduction, toxin production, and bypassing host defense mechanisms. The second group involves those factors related to the defense capacity of the host including local and systemic defense mechanisms. The last group contains environmental determinants of exposure such as size, time, and location of the surgical wound that can provide an opportunity for the bacteria to enter the surgical wound, overcome the local defense system, sustain their presence, and replicate and initiate local as well as systemic inflammatory reactions of the host. The use of iodine impregnated skin incise drapes shows decreased skin bacterial counts but no correlation has been established with SSI. However, no recommendations regarding the use of skin barriers can be made (see this Workgroup, Question 27)

A True Random Number Generator for Probabilistic Computing using Stochastic Magnetic Actuated Random Transducer Devices

Magnetic tunnel junctions (MTJs), which are the fundamental building blocks of spintronic devices, have been used to build true random number generators (TRNGs) with different trade-offs between throughput, power, and area requirements. MTJs with high-barrier magnets (HBMs) have been used to generate random bitstreams with $\lesssim$ 200~Mb/s throughput and pJ/bit energy consumption. A high temperature sensitivity, however, adversely affects their performance as a TRNG. Superparamagnetic MTJs employing low-barrier magnets (LBMs) have also been used for TRNG operation. Although LBM-based MTJs can operate at low energy, they suffer from slow dynamics, sensitivity to process variations, and low fabrication yield. In this paper, we model a TRNG based on medium-barrier magnets (MBMs) with perpendicular magnetic anisotropy. The proposed MBM-based TRNG is driven with short voltage pulses to induce ballistic, yet stochastic, magnetization switching. We show that the proposed TRNG can operate at frequencies of about 500~MHz while consuming less than 100~fJ/bit of energy. In the short-pulse ballistic limit, the switching probability of our device shows robustness to variations in temperature and material parameters relative to LBMs and HBMs. Our results suggest that MBM-based MTJs are suitable candidates for building fast and energy-efficient TRNG hardware units for probabilistic computing.Comment: 10 pages, 10 figures, Accepted at ISQED 2023 for poster presentatio

Intraoperative Vancomycin Use in Spinal Surgery: Single Institution Experience and Microbial Trends.

Study Design. Retrospective Case Series.Objective. To demonstrate the microbial trends of spinal surgical site infections(SSI) in patients who had previously received crystallized vancomycin in the operative bed.Summary of Background Data. Prior large, case control series demonstrate the significant decrease in SSI with the administration of vancomycin in the wound bed.Methods. A single institution, electronic database search was conducted for all spinal surgery patients who had received prophylactic crystalline vancomycin powder in the wound bed. Patient\u27s with a prior history of wound infection, intrathecal pumps, or spinal stimulators were excludedResults. 981 consecutive patients (494 male, 487 female, mean age 59.4 years, range 16-95 years) were identified from January 2011 to June 2013. The average dose of vancomycin powder was 1.13 grams(range: 1-6 grams). 66 patients (6.71%) were diagnosed with a SSI of which 51 patients had positive wound cultures (5.2%). Of the 51 positive cultures the most common organism was Staphylococcus aureus. The average dose of vancomycin was 1.3 grams in the 38 cases where a gram-positive organism was cultured. A number of gram-negative infections were encountered such as Serratia marcescens, Enterobacter aerogenes, Bacteroides fragilis, Enterobacter cloacae, Citrobacter koseri and Pseudomonas aeruginosa. The average dose of vancomycin was 1.2 grams in 23 cases where a gram negative infection was cultured. 15 of the 51 (29.4%) positive-cultures were polymicrobial. 8 (53%) of these 15 polymicrobial cultures contained three or more distinct organisms.Conclusion. Prophylactic intraoperative vancomycin use in the wound bed in spinal surgery may increase the incidence of gram-negative or polymicrobial spinal infections. The use of intraoperative vancomycin may correlate with postoperative seromas, due to the high incidence of non-positive cultures. Large, randomized, prospective trials are needed to demonstrate causation and dose-response relationship