The Effect of Obesity on Hemiarthroplasty and Total Hip Arthroplasty for Femoral Neck Fractures.

Obesity is a well-recognized global epidemic that can lead to longer operative times as well as a greater technical demand. Despite this, the available literature evaluating the impact of obesity on hip hemiarthroplasty (HA) and total hip arthroplasty (THA) when treating fractures about the femoral neck is scarce. Between 2015 and 2018, we retrospectively reviewed all patients that had a HA or THA performed as treatment for an isolated fracture of the femoral neck. Patients were classified as obese and nonobese depending on current body mass index (BMI) when the index procedure was performed. Preoperative and postoperative variable were obtained from the electronic medical record. A total of 157 patients underwent hip HA or THA for an isolated fracture of the femoral neck. In those patients undergoing HA, obesity was associated with an increase in operative times (P = 0.021) and was associated with a nonsignificant increase in total operating room time (P = 0.088) and duration of anesthesia (P = 0.14). In those patients undergoing THA, obesity was associated with longer operative times (P = 0.043), total operating room time (P = 0.032), and duration of anesthesia (P = 0.045). There were no significant differences in complication rates postoperatively between obese and non-obese patients undergoing either procedure. The treatment of isolated fractures of the femoral neck with HA or THA leads to an increase in operative time without an increase in postoperative complications in obese patients.

The First Case of Bridge-Enhanced Anterior Cruciate Ligament (ACL) Repair (BEAR) Procedure in Mississippi.

In the past, surgical treatment of anterior cruciate ligament (ACL) tears has mainly involved reconstruction using allografts and autografts. The relatively new FDA-approved bridge-enhanced ACL repair (BEAR) procedure allows the body to use its innate healing properties to help repair the ACL using an absorbable protein-based implant. The procedure is currently being offered by surgeons in 44 states. This case describes the first BEAR procedure performed in the state of Mississippi. A 47-year-old female of normal BMI presented to the orthopedic clinic with a chief complaint of right knee pain. The patient stated that she felt unstable on the injured knee, and the patient had positive anterior drawer and Lachman's tests on physical examination. MRI of the knee one month after injury revealed full-thickness ACL rupture. The patient underwent arthroscopic bridge-enhanced ACL repair in the right knee 43 days after the initial injury. The patient reported positive progress in her healing process at her three-month follow-up, and MRI at the three-month follow-up showed successful repair of the patient's ACL. At six months post-operatively, the patient reported that she is still doing well, and she feels that the stability of her right knee has improved. This case highlights an early trend towards repairs instead of reconstructions in ACL injuries for candidates that meet the following requirements: within 50 days of injury and have an intact tibial stump as recommended by the implant manufacturers.

Efficient trapping and destruction of SARS-CoV-2 using PECO-assisted Molekule air purifiers in the laboratory and real-world settings.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted human-to-human via aerosols and air-borne droplets. Therefore, capturing and destroying viruses from indoor premises are essential to reduce the probability of human exposure and virus transmission. While the heating, ventilation, and air conditioning (HVAC) systems help in reducing the indoor viral load, a targeted approach is required to effectively remove SARS-CoV-2 from indoor air to address human exposure concerns. The present study demonstrates efficient trapping and destruction of SARS-CoV-2 via nano-enabled filter technology using the UV-A-stimulated photoelectrochemical oxidation (PECO) process. Aerosols containing SARS-CoV-2 were generated by nebulization inside an air-controlled test chamber where an air purifier (Air Mini+) was placed. The study demonstrated the efficient removal of SARS-CoV-2 (99.98 %) from the test chamber in less than two minutes and PECO-assisted destruction (over 99%) on the filtration media in 1 h. Furthermore, in a real-world scenario, the Molekule Air-Pro air purifier removed SARS-CoV-2 (a negative RT-qPCR result post-running the filter device) from the circulating air in a COVID-19 testing facility. Overall, the ability of two FDA-approved class II medical devices, Molekule Air-Mini+ and Air-Pro air purifiers, to remove and destroy SARS-CoV-2 in indoor settings was successfully demonstrated. The study indicates that as the "tripledemic" of COVID-19, influenza, and respiratory syncytial virus (RSV) overwhelm the healthcare facilities in the USA, the use of a portable air filtration device will help contain the spread of the viruses in close door facilities, such as in schools and daycare facilities.

Reactive Oxygen Species Mediate Activity-Regulated Dendritic Plasticity Through NADPH Oxidase and Aquaporin Regulation.

Neurons utilize plasticity of dendritic arbors as part of a larger suite of adaptive plasticity mechanisms. This explicitly manifests with motoneurons in the Drosophila embryo and larva, where dendritic arbors are exclusively postsynaptic and are used as homeostatic devices, compensating for changes in synaptic input through adapting their growth and connectivity. We recently identified reactive oxygen species (ROS) as novel plasticity signals instrumental in this form of dendritic adjustment. ROS correlate with levels of neuronal activity and negatively regulate dendritic arbor size. Here, we investigated NADPH oxidases as potential sources of such activity-regulated ROS and implicate Dual Oxidase (but not Nox), which generates hydrogen peroxide extracellularly. We further show that the aquaporins Bib and Drip, but not Prip, are required for activity-regulated ROS-mediated adjustments of dendritic arbor size in motoneurons. These results suggest a model whereby neuronal activity leads to activation of the NADPH oxidase Dual Oxidase, which generates hydrogen peroxide at the extracellular face; aquaporins might then act as conduits that are necessary for these extracellular ROS to be channeled back into the cell where they negatively regulate dendritic arbor size.

The Effect of Obesity on Operative Time and Postoperative Complications for Peritrochanteric Femur Fractures.

Introduction The high prevalence of obesity among adults in the United States presents significant challenges to orthopedic surgeons. Obesity has been shown to increase operative time and complications in both elective and nonelective orthopedic surgeries. Despite this, there is a lack of literature evaluating the effect obesity has on operative time and postoperative complications following peritrochanteric fracture surgery. Methods and Materials We performed a retrospective review of patients who underwent isolated operative stabilization of a peritrochanteric femur fracture at our urban level one trauma center between 2010 and 2018. Patients were divided into an obese group, as defined by a body mass index (BMI) equal to or greater than 30 kg/m2, and a nonobese group, as defined by a BMI less than 30 kg/m2. Operative timing variables including time to surgery, operative time, total operating room (OR) time, anesthesia time, and fluoroscopy time were collected. Postoperative variables evaluated including the presence of a major postoperative complication within 90 days of surgery, the need for repeat surgery within 90 days, and the need for surgery due to an infection within 90 days were collected. Results A total of 175 patients were included in this retrospective review. Thirty-seven patients were included in the obese group, and 138 were included in the nonobese group. Obesity was associated with a significantly (p = 0.002) longer operative time, total OR time (p = 0.0001), anesthesia time (p = 0.00006), and fluoroscopy time (p = 0.0001). There was no significant difference (p > 0.05) in postoperative variables between the obese and nonobese group. The 90-day major postoperative complication rate was 10.8% in the obese group and 10.9% in the nonobese group. Both repeat surgery and surgery for infection within 90 days were 2.7% in the obese group and 1.4% in the nonobese group. Conclusion The treatment of peritrochanteric femur fractures in obese patients is associated with a significantly longer operative time, total OR time, anesthesia time, and fluoroscopy time, but no difference in major postoperative complications when compared to nonobese patients.

Patient Mortality in Geriatric Distal Femur Fractures.

OBJECTIVES: To estimate 1-year mortality rates in elderly patients who undergo operative treatment for distal femur fractures and identify potential risk factors for mortality. DESIGN: Retrospective chart review. SETTING: Level 1 and Level 2 trauma centers. PATIENTS/PARTICIPANTS: Two hundred eighty-three elderly patients (average age 76.0 years ± 9.8) who sustained distal femur fractures between 2002 and 2012. INTERVENTION: Fracture fixation of the distal femur. MAIN OUTCOME MEASURE: Survival up to 1 year after surgery. RESULTS: The 1-year mortality rate for distal femur fractures in elderly patients was 13.4%. There were no statistically significant differences in overall mortality between native bone and periprosthetic fractures, intramedullary nail or open reduction internal fixation, or across Orthopaedic Trauma Association fracture classifications. Overall patient mortality was significantly higher at 30 days (P = 0.036), 6 months (P = 0.019), and 1 year (P = 0.018), when surgery occurred more than 2 days from the injury. Mean Charlson Comorbidity Index scores were significantly lower in survivors versus nonsurvivors at all time intervals (30 days, P = 0.023; 6 months, P = 0.001 and 1 year P ≤ 0.001). A time to surgery of more than 2 days, regardless of baseline illness, did not result in improved survivability at 1 year. CONCLUSIONS: Overall mortality for distal femur fractures was 13.4% in the elderly population. A surgical treatment more than 2 days after injury was associated with increased patient mortality. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Intra- and interindividual variations mask interspecies variation in the microbiota of sympatric peromyscus populations.

Using populations of two sympatric Peromyscus species, we characterized the importance of the host species, physiology, environment, diet, and other factors in shaping the structure and dynamics of their gut microbiota. We performed a capture-mark-release experiment in which we obtained 16S rRNA gene sequence data from 49 animals at multiple time points. In addition, we performed 18S rRNA gene sequencing of the same samples to characterize the diet of each individual. Our analysis could not distinguish between the two species of Peromyscus on the basis of the structures of their microbiotas. However, we did observe a set of bacterial populations that were found in every animal. Most notable were abundant representatives of the genera Lactobacillus and Helicobacter. When we combined the 16S and 18S rRNA gene sequence analyses, we were unable to distinguish the communities on the basis of the animal's diet. Furthermore, there were no discernible differences in the structure of the gut communities based on the capture site or their developmental or physiological status. Finally, in contrast to humans, where each individual has a unique microbiota when sampled over years, among the animals captured in this study, the uniqueness of each microbiota was lost within a week of the original sampling. Wild populations provide an opportunity to study host-microbiota interactions as they originally evolved, and the ability to perform natural experiments will facilitate a greater understanding of the factors that shape the structure and function of the gut microbiota.

A role for suppressed incisor cuspal morphogenesis in the evolution of mammalian heterodont dentition.

Changes in tooth shape have played a major role in vertebrate evolution with modification of dentition allowing an organism to adapt to new feeding strategies. The current view is that molar teeth evolved from simple conical teeth, similar to canines, by progressive addition of extra "cones" to form progressively complex multicuspid crowns. Mammalian incisors, however, are neither conical nor multicuspid, and their evolution is unclear. We show that hypomorphic mutation of a cell surface receptor, Lrp4, which modulates multiple signaling pathways, produces incisors with grooved enamel surfaces that exhibit the same molecular characteristics as the tips of molar cusps. Mice with a null mutation of Lrp4 develop extra cusps on molars and have incisors that exhibit clear molar-like cusp and root morphologies. Molecular analysis identifies misregulation of Shh and Bmp signaling in the mutant incisors and suggests an uncoupling of the processes of tooth shape determination and morphogenesis. Incisors thus possess a developmentally suppressed, cuspid crown-like morphogenesis program similar to that in molars that is revealed by loss of Lrp4 activity. Several mammalian species naturally possess multicuspid incisors, suggesting that mammals have the capacity to form multicuspid teeth regardless of location in the oral jaw. Localized loss of enamel may thus have been an intermediary step in the evolution of cusps, both of which use Lrp4-mediated signaling.