Standard versus low-dose computed tomography for assessment of acetabular fracture reduction using novel step and gap measurement technique.

PURPOSE: Quality of reduction is of paramount importance after acetabular fracture and is best assessed on computed tomography (CT). A recently proposed measurement technique for assessment of step and gap displacement is reproducible but has not been validated. The purpose of this study is to validate a well-established measurement technique against known displacements and to determine if it can be used with low dose CT. METHODS: Posterior wall acetabular fractures were created in 8 cadaveric hips and fixed at known step and gap displacements. CT was performed at multiple radiation doses for each hip. Four surgeons measured step and gap displacement for each hip at all doses, and the measurements were compared to known values. RESULTS: There were no significant differences in measurements across surgeons, and all measurements were found to have positive agreement. Measurement error < 1.5 mm was present in 58% of gap measurements and 46% of step measurements. Only for step measurements at a dose of 120 kVp did we observe a statistically significant measurement error. There was a significant difference in step measurements made by those with greater and those with fewer years in practice. CONCLUSION: Our study suggests this technique is valid and accurate across all doses. This is important as it may reduce the amount of radiation exposure for patients with acetabular fractures.

A randomized controlled trial of an online health tool about Down syndrome.

PURPOSE: We sought to determine if a novel online health tool, called Down Syndrome Clinic to You (DSC2U), could improve adherence to national Down syndrome (DS) guidelines. We also sought to determine if primary care providers (PCPs) and caregivers are satisfied with this personalized online health tool. METHODS: In a national, randomized controlled trial of 230 caregivers who had children or dependents with DS without access to a DS specialist, 117 were randomized to receive DSC2U and 113 to receive usual care. The primary outcome was adherence to five health evaluations indicated by national guidelines for DS. DSC2U is completed electronically, in all mobile settings, by caregivers at home. The outputs-personalized checklists-are used during annual wellness visits with the patient's PCP. RESULTS: A total of 213 participants completed a 7-month follow-up evaluation. In the intention-to-treat analysis, the intervention group had a 1.6-fold increase in the number of indicated evaluations that were recommended by the primary care provider or completed compared with controls. Both caregivers and PCPs reported high levels of satisfaction with DSC2U. CONCLUSIONS: DSC2U improved adherence to the national DS health-care guidelines with a novel modality that was highly valued by both caregivers and PCPs.

Unusual case report of concomitant lunate and scaphoid fractures without associated dislocation in a 16-year-old male.

INTRODUCTION AND IMPORTANCE: Lunate fractures without associated dislocations are rare injuries, combination scaphoid-lunate fractures without an associated dislocation are even more rare of which few are reported in the literature. CASE PRESENTATION: This case report describes a 16-year-old otherwise healthy male with ipsilateral scaphoid and lunate fractures after punching a goalpost with his left hand, for which he had surgical management. This patient had a successful treatment with two headless compression screws through a single extended carpal tunnel approach. Surgery was performed within two weeks of injury after initially immobilized with a thumb spica splint. The postoperative period was complicated by noncompliance with weight-bearing status and missed three-month followup. However, by six months, subsequent visits demonstrated radiographic and clinical healing as well as full wrist range of motion without any other sequelae. CLINICAL DISCUSSION: This case offers more evidence regarding this rare injury. Lunate fractures and scaphoid fractures can both be treated with open reduction and internal fixation using headless compression screws, however little evidence exists when it comes to treating them in combination. CONCLUSION: The use of headless compression screws through a single extended carpal tunnel approach led to clinical and radiographic healing in a 16 year-old-male with combined scaphoid and lunate fractures at 6 month follow up.

Osteochondroma of the superomedial scapula managed with a novel muscle sparing approach: case report and review of literature.

Osteochondromas are a common type of benign primary bone tumor rarely occurring in the scapula. When it is symptomatic, surgical removal is recommended. There are multiple approaches for surgical excision that can be used depending on the location and size of the tumor. We present a case of a 14-year-old female who was seen in the orthopedic clinic with right shoulder pain, mechanical symptoms and medial scapular winging due to a superomedial osteochondroma of the scapula. A novel superior approach to the superomedial ventral surface of the scapula was utilized to excise the tumor with good clinical results.

A Comparative Study of Traditional Technique Guide versus Virtual Reality in Orthopedic Trauma Training.

Background: Medical and surgical education is an expansive field fraught with many challenges. Technology such as virtual reality could be a new venue that can offer a solution to improve surgical training. Objective: The objective of this prospective, blinded study was to evaluate virtual reality as a training model for orthopedic surgery and surgical training at large. Methods: Fourth-year medical students with novice skills volunteered to participate in this observer-blinded 1:1 randomized controlled trial. They had no prior experience in tibia intramedullary nail (IMN) surgery. They were randomized into traditional technique guide education and virtual reality. The participants were timed on their mock surgery, and a blinded observer was utilized to subjectively grade their performance throughout the procedure using the Global Assessment 5-point Rating Scale and Procedure-Specific Checklist. Results: Thirty-eight participants were recruited and randomized into virtual reality (19) and traditional (19) groups. There were trends in all categories favoring the virtual reality group. The VR group had improved time to completion (9.6 minutes vs 12.2 minutes, P = 0.034) and reduced need for corrections within the mock procedure (2.2 vs 2.5; P = 0.05). Conclusion: Virtual reality training was more effective than traditional training in learning and completing the steps of the tibia IMN surgery for novice medical students. Virtual reality training may be a useful method to augment orthopedic education and surgical training.

Diagnostic Utility of Cerebrospinal Fluid White Blood Cell Components for the Identification of Bacterial Meningitis in Infants.

BACKGROUND: To evaluate the diagnostic and predictive utility of cerebrospinal fluid (CSF) white blood cell (WBC) components in the diagnosis of bacterial meningitis in infants discharged from the neonatal intensive care unit (NICU). METHODS: We identified a cohort of infants discharged from a Pediatrix NICU between 1997 and 2020 who did not have an immunodeficiency, had at least 1 CSF culture collected within the first 120 days of life, and at least 1 CSF laboratory specimen obtained on the day of culture collection. We only included an infant's first CSF culture and excluded cultures from CSF reservoirs and those growing contaminants or nonbacterial organisms. We examined the utility of CSF WBC components to diagnose or predict bacterial meningitis by calculating sensitivity, specificity, positive and negative predictive values, likelihood ratios, and area under the receiver operating curve (AUC) at different cutoff values for each parameter. We performed subgroup analysis excluding infants treated with antibiotics the day before CSF culture collection. RESULTS: Of the 20 756 infants that met the study inclusion criteria, 320 (2%) were diagnosed with bacterial meningitis. We found (AUC [95% CI]) CSF WBC count (0.76 [0.73-0.79]), CSF neutrophil count (0.74 [0.70-0.78]), and CSF neutrophil percent (0.71 [0.67-0.75]) had the highest predictive values for bacterial meningitis, even when excluding infants with early antibiotic administration. CONCLUSIONS: No single clinical prediction rule had the optimal discriminatory power for predicting culture-proven bacterial meningitis, and clinicians should be cautious when interpreting CSF WBC parameters in infants with suspected meningitis.

Virtual Reality Training in Unicompartmental Knee Arthroplasty: A Randomized, Blinded Trial.

OBJECTIVE: The objective of this study was to evaluate the effectiveness of immersive virtual reality training in orthopedic surgery education in comparison to the standard technique guide for fixed-bearing medial unicompartmental knee arthroplasty DESIGN: Participants included 22 orthopedic surgery residents who were randomized to undergo fixed-bearing medial unicompartmental knee arthroplasty (UKA) surgical training with either an immersive virtual reality technology or by studying the traditional technique guide. Participants were randomized within their training year via block randomization. Participants then performed a medial UKA on a SawBone model using standard industry system surgical trays and equipment. Proficiency, timing, number of errors made, and subjective data were obtained during and after the SawBone procedure. A blinded observer was utilized to obtain objective data. SETTING: Community Memorial Health System, a primary clinical care institution in Ventura, California. PARTICIPANTS: Twenty-two orthopedic surgery residents were randomly selected. There were 7 PGY-1 residents (3 TG, 4 VR), 7 PGY-2s (4 TG, 3 VR), 3 PGY-3s (1 TG, 2 VR), 3 PGY-4s (2 TG, 1 VR), and 2 PGY-5s (1 TG, 1 VR) in total. Eligibility criteria were 1) an active orthopedic surgery resident, 2) no prior immersive VR surgical training, and 3) no prior experience with the Zimmer PPK implants or its technique guide. All participants completed the study. RESULTS: Residents were randomized evenly in the virtual reality (n = 11) and technique guide groups (n = 11). Analysis showed that residents who trained with the immersive VR executed significantly more steps correctly (33 vs. 27, p < 0.01) and completed their procedure in significantly faster time (26.7 vs. 35.4 minutes, p < 0.01). They also scored higher in all global assessment categories reaching significance in 4 of 5 categories. Subjective questionnaire responses demonstrated positive feedback within both groups with a trend toward virtual reality. No adverse events were recorded. CONCLUSIONS: Immersive virtual reality was more effective than traditional training for the participants of this study. There are numerous potential applications of this technology and it provides an alternative learning modality to accommodate different learning styles.

Distal fibular excision: A review of the literature and presentation of our reconstruction technique case series.

Distal fibula resection is a procedure that has been described as early as 1938 for the treatment of neoplastic lesions. There have been several techniques described for the reconstruction of the remaining tibiotalar joint to prevent deformity and maintain as much function as possible. While these reconstruction techniques provide an option for limb salvage with the removal of disease, patients are faced with chronic pain, loss of function, valgus instability, need for long term orthosis, early arthritis, or significant morbidity related to proximal dissection and disruption of native knee anatomy. We present a case series that is compliant with PROCESS1 criteria to demonstrate the effective treatment with distal fibular excision and a reconstruction technique inspired by the original Tommy John procedure of the elbow. This procedure has allowed these two patients long-term stability of the ankle, maintenance of full function, and high levels of function. The first case is a 23-year-old female with high-grade osteosarcoma and the second patient is a 19-year-old female with Ewing sarcoma. Details of the procedure as well as clinical and radiographic follow up of these two patients will be described.

Elevated salivary IgA, decreased anxiety, and an altered oral microbiota are associated with active participation on an undergraduate athletic team.

BACKGROUND: Previous reports indicate that regular, but not excessive, exercise can moderate the response to anxiety and alter the immune response, therefore we hypothesized that college student athletes who were actively participating on an NCAA Division III athletics team ("in-season") would have lower levels of anxiety and higher salivary IgA levels than similar college athletes who were in their "off-season". NCAA Division III athletes participate in athletics at a level of intensity that is more moderate compared to other NCAA divisions. Alterations in the microbiome have been associated with alterations in psychosocial well-being and with exercise. Therefore, we also proposed that the oral microbiota would be different in "in-season" versus "off-season" athletes. METHOD: In this pilot study, nineteen female students participating on a NCAA Division III athletic team (hockey="in-season"; soccer="off-season") were compared for level of fitness (modified Balke test of VO2 max), salivary IgA levels by immunoassay, anxiety (using a GAD-7 survey), salivary cortisol levels by immunoassay, and numbers of culturable bacteria by growth of CFU/ml on blood agar, mitis salivarius agar and Staphylococcus 110 agar. RESULTS: The proportion of subjects reporting "severe anxiety" on an anxiety scale (GAD-7) were significantly greater in the "off-season" group compared to the "in-season" group (p=0.047, Chi-squared test). "In-season" athletes had significantly higher salivary IgA/total protein levels than "off-season" athletes (one-sided Student's t-test; p=0.03). Cortisol levels were not significantly different in the two groups. The total culturable bacteria counts were higher among "in-season" athletes (p=0.0455, Wilcoxon Rank Sum test), as measured by CFUs on blood agar plates, an estimate of total culturable bacteria, including pathogenic and non-pathogenic bacteria. In contrast, there was a decrease in the growth of bacteria from the oral cavity of the "in-season" athletes, when the growth of bacteria on mitis salivarius agar (primarily oral streptococcus) was measured (p=0.0006, Wilcoxon Rank Sum test). There was a negative correlation (Spearman Rank correlation coefficient=-0.651, p=0.0018 one-sided) between high IgA levels and the growth of bacteria on mitis salivarius agar in the combined group of "in-season" and "off-season" athletes, suggesting a protective response of high IgA levels to the typical oral pathogenic bacteria. Anxiety levels (GAD-7) in the "in-season" group were positively correlated with growth of oral bacteria on blood agar (Spearman Rank correlation coefficient of 0.622 for "in-season", p value=0.033 one-sided) and mitis salivarius agar (Spearman Rank correlation coefficient=0.671 for "in-season, p value=0.021 one-sided), and negatively correlated in "off-season" athletes on blood agar (-0.689 for "off-season", p value=0.028 one-sided), supporting the hypothesis that the microbiota are distinct in "in-season" and "off-season" athletes and may be associated with anxiety levels. CONCLUSION: These findings are supportive of the hypothesis that participation in college level athletics has a positive effect on student-athlete health, specifically enhanced protective oral immunity, reduced anxiety, and alterations in oral microbial populations.

Adaptation of yellow fever virus 17D to Vero cells is associated with mutations in structural and non-structural protein genes.

Serial passaging of yellow fever virus 17D in Vero cells was employed to derive seed material for a novel inactivated vaccine, XRX-001. Two independent passaging series identified a novel lysine to arginine mutation at amino acid 160 of the envelope protein, a surface-exposed residue in structural domain I. A third passage series resulted in an isoleucine to methionine mutation at residue 113 of the NS4B protein, a central membrane spanning region of the protein which has previously been associated with Vero cell adaptation of other mosquito-borne flaviviruses. These studies confirm that flavivirus adaptation to growth in Vero cells can be mediated by structural or non-structural protein mutations.

Solution structure of the envelope protein domain III of dengue-4 virus.

The disease dengue (DEN) is caused by four serologically related viruses termed DEN1, DEN2, DEN3 and DEN4. The structure of the ectodomain of the envelope protein has been determined previously for DEN2 and DEN3 viruses. Using NMR spectroscopic methods, we solved the solution structure of domain III (ED3), the receptor-binding domain, of the envelope protein of DEN4 virus, human strain 703-4. The structure shows that the nine amino acid changes in ED3 that separate the sylvatic and human DEN4 strains are surface exposed. Important structural differences between DEN4-rED3 and ED3 domains of DEN2, DEN3 and other flaviviruses are discussed.