Factors that determine first intubation attempt success in high-risk neonates.

BACKGROUND: Approximately 50% of all neonatal endotracheal intubation attempts are unsuccessful and associated with airway injury and cardiorespiratory instability. The aim of this study was to describe intubation practice at a high-risk Neonatal Intensive Care Unit (NICU) and identify factors associated with successful intubation at the first attempt. METHODS: Retrospective cohort study of all infants requiring intubation within the Royal Children's Hospital NICU over three years. Data was collected from the National Emergency Airway Registry for Neonates (NEAR4NEOS). Outcomes were number of attempts, level of operator training, equipment used, difficult airway grade, and clinical factors. Univariate and multivariate analysis were performed to determine factors independently associated with first attempt success. RESULTS: Three hundred and sixty intubation courses, with 538 attempts, were identified. Two hundred and twenty-five (62.5%) were successful on first attempt, with similar rates at subsequent attempts. On multivariate analysis, increasing operator seniority increased the chance of first attempt success. Higher glottic airway grades were associated with lower chance of first attempt success, but neither a known difficult airway nor use of a stylet were associated with first attempt success. CONCLUSION: In a NICU with a high rate of difficult airways, operator experience rather than equipment was the greatest determinant of intubation success. IMPACT: Neonatal intubation is a high-risk lifesaving procedure, and this is the first report of intubation practices at a quaternary surgical NICU that provides regional referral services for complex medical and surgical admissions. Our results showed that increasing operator seniority and lower glottic airway grades were associated with increased first attempt intubation success rates, while factors such as gestational age, weight, stylet use, and known history of difficult airway were not. Operator factors rather than equipment factors were the greatest determinants of first attempt success, highlighting the importance of team selection for neonatal intubations in a high-risk cohort of infants.

Neonatal clinical examination and selective ultrasound screening are not reliable for the early diagnosis of hip dysplasia: A retrospective cohort study.

AIM: To compare the incidence, clinical features and timing of initial treatment of early- and later-presenting developmental dysplasia of the hip (DDH) in infancy in the context of a risk-based selective ultrasound screening programme. METHODS: We conducted a retrospective observational study of infants born at a tertiary perinatal centre in Melbourne, Australia, between July 2016 and June 2020 and treated for DDH up to 18 months of age at a tertiary paediatric centre. The incidence of DDH was calculated for early- and later-presenting cases. Clinical features and ultrasound indications were analysed using multivariate logistic regression. RESULTS: There were 192 infants with DDH requiring treatment, 100 (52%) of which were not detected by universal neonatal hip examination and selective ultrasound screening based on risk factors (overall incidence 6.3 per 1000 livebirths). The median age at which treatment was commenced was delayed by 8 weeks for the later-presenting group compared to those detected through screening (16.7 vs. 7.9 weeks, P < 0.001). Skin crease asymmetry was associated with later presentation (adjusted odds ratio (aOR) 44.03, 95% confidence interval (CI) 9.99-333), whilst breech presentation (aOR 0.08, 95% CI 0.02-0.26) and Barlow/Ortolani test positivity (aOR 0.06, 95% CI 0.01-0.25) were associated with early presentation. Only 39 (1.45%) infants receiving a screening ultrasound had DDH. CONCLUSION: Approximately half of all infants with DDH were not detected by combining risk-based selective ultrasound screening with neonatal clinical findings, highlighting the failure of this screening method to reliably detect a significant proportion of dysplastic infant hips.

MRI Predictors of Residual Dysplasia in Developmental Dysplasia of the Hip Following Open and Closed Reduction.

BACKGROUND: Following open or closed reduction for children with developmental dysplasia of the hip, there remains a significant risk of residual acetabular dysplasia which can compromise the long-term health of the hip joint. The purpose of this study was to use postoperative in-spica magnetic resonance imaging (MRI) data to determine factors predictive of residual acetabular dysplasia at short-term follow-up. METHODS: We retrospectively reviewed 63 hips in 48 patients which underwent closed or open reduction and spica casting for developmental dysplasia of the hip. MRI performed in-spica at ∼3-week follow-up were used to assess 11 validated metrics and 2 subjective factors. Acetabular index (AI) was measured on anteroposterior pelvic radiographs at 2-year postoperative follow-up. Binary logistic regression was then used to identify variables predictive of residual dysplasia, defined as an AI greater than the 90th percentile for age based on historic normative data. RESULTS: Average age at surgical reduction was 9.3±3.2 months. 58.7% (37/63) of reductions were open. A total of 43 (68.3%) hips demonstrated residual acetabular dysplasia at 2 years postoperatively based on normative values. In those with persistent dysplasia, patients were on average older at the time of reduction (10.0 mo±3.2 vs. 8.0 mo±2.8, P=0.010) and more likely female (88.4% vs. 60.0%, P=0.010). Patients with residual dysplasia were more likely to have mild subluxation on postoperative MRI (40.0% vs. 10.5%, P=0.022). Hips with a cartilaginous acetabular index (CAI) of >23 degrees were 7.6 times more likely to develop residual dysplasia. Type of reduction (ie, closed vs. open) did not appear to influence the rate of residual dysplasia (P=0.682). CONCLUSION: In this series, the rate of residual dysplasia after surgical reduction was higher than most previous reports, with no appreciable difference between closed and open reductions. Older age, female sex, and a higher CAI were associated with a greater risk of persistent radiographic dysplasia. In particular, hips with a CAI >23 degrees were 7.6 times more likely to be dysplastic at 2-year follow-up. LEVEL OF EVIDENCE: Level III.

Study Groups and POSNA: A Review of Podium Presentations From 2006 to 2020.

BACKGROUND: Study groups are multicenter collaborations aimed at improving orthopaedic decision-making through higher-powered, more generalizable studies. New research is disseminated through peer-reviewed literature and academic meetings, including the Pediatric Orthopaedic Society of North America (POSNA) annual meeting, which brings together academic and medical professionals in pediatric orthopaedics. The goal of this study was to identify patterns in podium presentations (PP) at the POSNA annual meeting resulting from multicenter study groups during a 15-year period. METHODS: A total of 2065 PP from the 2006 to 2020 POSNA annual meetings were identified. The abstracts of each PP were reviewed to determine if they resulted from a multicenter study group and for characteristics including subspecialty focus. PP from 2006 to 2018 were further reviewed for publication in academic journals. Pearson correlation was used to assess change in the number of PP resulting from study groups overtime. Univariate analysis was used to compare characteristics of PP based on study group involvement (significance P<0.05). RESULTS: The proportion of PP resulting from study groups increased from 2.2% (n=2) in 2006 to 9.4% in 2020 (n=16) (R2=0.519, P=0.002). Of the PP resulting from study groups, 52.9% focused on spine, 26.5% on hip, 2.9% on sports, and 2.0% on trauma. This is compared with a distribution of 16.7% (P<0.001) spine, 15.9% (P=0.005) hip, 9.5% (P=0.026) sports, and 14.6% (P<0.001) trauma focus of PP not from study groups. There was no difference in publication rate of PP resulting from study groups compared with those that were not (69.1% vs. 66.2%, P=0.621). CONCLUSIONS: In the 15-year period from 2006 to 2020, there was a nearly 5-fold increase in the proportion of POSNA PP resulting from study groups. Spine surgery is disproportionately supported by study groups, suggesting that there is an opportunity to establish new study groups across the breadth of pediatric orthopaedics. LEVEL OF EVIDENCE: Level V.

Diversity of Sea Star-Associated Densoviruses and Transcribed Endogenous Viral Elements of Densovirus Origin.

A viral etiology of sea star wasting syndrome (SSWS) was originally explored with virus-sized material challenge experiments, field surveys, and metagenomics, leading to the conclusion that a densovirus is the predominant DNA virus associated with this syndrome and, thus, the most promising viral candidate pathogen. Single-stranded DNA viruses are, however, highly diverse and pervasive among eukaryotic organisms, which we hypothesize may confound the association between densoviruses and SSWS. To test this hypothesis and assess the association of densoviruses with SSWS, we compiled past metagenomic data with new metagenomic-derived viral genomes from sea stars collected from Antarctica, California, Washington, and Alaska. We used 179 publicly available sea star transcriptomes to complement our approaches for densovirus discovery. Lastly, we focus the study on sea star-associated densovirus (SSaDV), the first sea star densovirus discovered, by documenting its biogeography and putative tissue tropism. Transcriptomes contained only endogenized densovirus elements similar to the NS1 gene, while numerous extant densoviral genomes were recovered from viral metagenomes. SSaDV was associated with nearly all tested species from southern California to Alaska, and in contrast to previous work, we show that SSaDV is one genotype among a high diversity of densoviruses present in sea stars across the West Coast of the United States and globally that are commonly associated with grossly normal (i.e., healthy or asymptomatic) animals. The diversity and ubiquity of these viruses in sea stars confound the original hypothesis that one densovirus is the etiological agent of SSWS.IMPORTANCE The primary interest in sea star densoviruses, specifically SSaDV, has been their association with sea star wasting syndrome (SSWS), a disease that has decimated sea star populations across the West Coast of the United States since 2013. The association of SSaDV with SSWS was originally drawn from metagenomic analysis, which was further studied through field surveys using quantitative PCR (qPCR), with the conclusion that it was the most likely viral candidate in the metagenomic data based on its representation in symptomatic sea stars compared to asymptomatic sea stars. We reexamined the original metagenomic data with additional genomic data sets and found that SSaDV was 1 of 10 densoviruses present in the original data set and was no more represented in symptomatic sea stars than in asymptomatic sea stars. Instead, SSaDV appears to be a widespread, generalist virus that exists among a large diversity of densoviruses present in sea star populations.

Entire-spine Magnetic Resonance Imaging Findings and Costs in Children With Presumed Adolescent Idiopathic Scoliosis.

BACKGROUND: Patients with adolescent idiopathic scoliosis (AIS) are commonly monitored for curve progression with spinal radiographs; however, the utility of magnetic resonance imaging (MRI) screening is unclear. The purpose of this study was to assess the findings of screening MRI for patients with a nonsurgical curve size ordered during routine clinical care and compare them with MRI ordered for patients with large curves as part of preoperative screening. METHODS: All consecutive patients with presumed AIS who underwent entire-spine MRI with a presumed diagnosis of idiopathic scoliosis at a single institution between 2017 and 2019 were retrospectively reviewed. Patients were stratified based on MRI indication into the following groups: preoperative evaluation, pain, neurological symptoms, abnormal radiographic curve appearance, rapidly progressive curve, and other. Neural axis abnormalities recorded included concern for tethered spinal cord, syringomyelia, and Chiari malformation. The MRI findings of preoperative patients with large curves were compared with all other patients. The number needed to diagnose (NND) a neurological finding was calculated in patients whose MRIs were ordered during routine clinical care. The amount charged for each patient undergoing entire-spine MRI was determined by review of our institution's Financial Decision Support system. RESULTS: There were 344 patients included in this study with 214 (62%) MRIs performed for preoperative evaluation. Although MRI abnormalities were found in 49% of patients, only 7.0% (24/344) demonstrated neural axis abnormalities with no difference between preoperative and other indications (P=0.37). For patients with nonsurgical curves undergoing MRI due to a complaint of back pain (n=28), there were no neural axis abnormalities, and a lower rate of disk herniation/degenerative changes detected compared with preoperative MRI (3.6% vs. 18%, P=0.06). Among the 15 patients undergoing MRI for a neurological concern, 1 had a neural axis abnormality that required surgical detethering. The NND for MRI to detect a neural axis abnormality that potentially required neurosurgical intervention in nonpreoperative patients with a neurological concern was 34.4. The average cost for MRI was $17,816 (range: $2601 to $22,411) with a total cost of $2,368,439 for nonsurgical curves. CONCLUSIONS: Entire-spine MRI for nonpreoperative indications including pain, abnormal radiographic curve appearance, and rapid curve progression has minimal utility for patients with AIS. For patients with neurological complaints, the NND a potentially treatment-altering finding with MRI is 34.4. LEVEL OF EVIDENCE: Level II-diagnostic.

A Gender Gap in Publishing? Understanding the Glass Ceiling in Pediatric Orthopaedic Surgery.

BACKGROUND: Women are underrepresented across most surgical specialties and especially in the field of orthopaedic surgery. Despite pediatric orthopaedic surgery being one of the most gender diverse subspecialties in orthopaedics, women may still face barriers to academic advancement. Research presentations at national meetings and publication record are important drivers of advancement in the field of academic orthopaedic surgery. The aim of this study is to assess whether research abstracts authored by women are less likely to be published than abstracts authored by men. METHODS: Abstracts from research podium presentations given at the Pediatric Orthopaedic Society of North America annual meetings from 2006 to 2020 were reviewed to assess research quality and determine basic study characteristics. For each abstract, author gender was determined through a search of institutional websites and professional networking websites for gender-specific pronouns. Resulting publications corresponding to the 2006 to 2018 were identified using a systematic search of PubMed and Google Scholar databases. Kaplan-Meier inverse survival analysis with log rank test were used to determine differences in publication rates based on whether the last (senior) author was female versus male. Multivariate, binary logistic regression was performed to assess factors predictive of eventual publication. RESULTS: One thousand five hundred and eighty-one of 1626 (97.2%) of abstracts from 2006 to 2020 had an identifiable last author gender, with 17.8% (281/1581) female. No differences in study quality were identified across genders including sample size, level of evidence, or impact factor of journal if leading to publication. Women were more likely to author abstracts in foot, ankle, or lower extremity surgery [17.8% (50/281) vs. 12.9% (168/1300), P=0.032] and less likely to author abstracts focusing on the hip [11.0% (31/281) vs. 17.1% (222/1300), P=0.012]. Abstracts with women as the last author were significantly less likely to be published compared with abstracts with men as the last author [59.6% (143/240) vs. 67.9% (783/1154), P=0.013]. Multivariate analysis demonstrated that last author female gender was predictive of a lower likelihood of publication (odds ratio: 0.684, 95% confidence interval: 0.513-0.912, P=0.010). Women were less likely to be the last author of abstracts presented by study groups [2.1% (6/281) vs. 5.5% (71/1300), P=0.019]. CONCLUSION: In pediatric orthopaedic surgery, abstracts authored by women are less likely to reach publication, despite no identifiable differences in study quality. Reasons for this discrepancy must be explored including insufficient mentorship, exclusion from study group participation, or potential bias against female researchers in the field of orthopaedic surgery. LEVEL OF EVIDENCE: Level IV.

Risk of Scoliosis Progression in Nonoperatively Treated Adolescent Idiopathic Scoliosis Based on Skeletal Maturity.

BACKGROUND: Hand radiographs for skeletal maturity staging are now frequently used to evaluate remaining growth potential for patients with adolescent idiopathic scoliosis (AIS). Our objective was to create a model predicting a patient's risk of curve progression based on modern treatment standards. METHODS: We retrospectively reviewed all AIS patients presenting with a major curve <50 degrees, available hand radiographs, and complete follow up through skeletal maturity at our institution over a 3-year period. Patients with growth remaining underwent rigid bracing of curves >25 degrees, whereas patients between 10 and 25 degrees were observed. Treatment success was defined as reaching skeletal maturity with a major curve <50 degrees. Four risk categories were identified based on likelihood of curve progression. RESULTS: Of 609 AIS patients (75.4% female) presenting with curves over 10 degrees and reaching skeletal maturity at most recent follow up, 503 (82.6%) had major thoracic curves. 16.3% (82/503) of thoracic curves progressed into surgical treatment range. The highest risk group (Sanders 1 to 6 and curve 40 to 49 degrees, Sanders 1 to 2 and curve 30 to 39) demonstrate a 30% success rate with nonoperative treatment. This constitutes an 111.1 times (95% confidence interval: 47.6 to 250.0, P<0.001) higher risk of progression to surgical range than patients in the lowest risk categories (Sanders 1 to 8 and curve 10 to 19 degrees, Sanders 3 to 8 and curve 20 to 29 degrees, Sanders 5 to 8 and curve 30 to 39 degrees). CONCLUSIONS: Skeletal maturity and curve magnitude have strong predictive value for future curve progression. The results presented here represent a valuable resource for orthopaedic providers regarding a patient's risk of progression and ultimate surgical risk. LEVEL OF EVIDENCE: Level III-retrospective cohort study.

What's New in Pain Management for Pediatric Orthopaedic Surgery.

BACKGROUND: Improving pain control and decreasing opioid prescription and usage continue to be emphasized across both pediatric and adult populations. The purpose of this review is to provide a comprehensive assessment of recent literature and highlight new advancements pertaining to pain control in pediatric orthopaedic surgery. METHODS: An electronic search of the PubMed database was performed for keywords relating to perioperative pain management of pediatric orthopaedic surgery. Search results were filtered by publication date for articles published between January 1, 2015 and December 1, 2020 and yielded 404 papers. RESULTS: A total of 32 papers were selected for review based upon new findings and significant contributions in the following categories: risk factors for increased opioid usage, opioid overprescribing and disposal, nonpharmacologic interventions, nonsteroidal anti-inflammatory drugs, peripheral nerve blocks, spine surgery specific considerations, surgical pathway modifications, and future directions. CONCLUSIONS: There have been many advances in pain management for pediatric patients following orthopaedic surgery. Rapid recovery surgical care pathways are associated with shorter length of stay and improved pain control in pediatric spine surgery. Opioid overprescribing continues to be common and information regarding safe opioid disposal practices should be routinely provided for pediatric patients undergoing surgery. LEVEL OF EVIDENCE: Level IV-literature review.

Rib-based Distraction Device Implantation Before Age 3 Associated With Higher Unplanned Rate of Return to the Operating Room.

BACKGROUND: Surgical treatment of early-onset scoliosis (EOS) with rib-based implants such as the vertical expandable prosthetic titanium rib (VEPTR) is associated with a high rate of complications including surgical site infection, skin breakdown, and implant migration. Many of these complications warrant the need for unplanned reoperations, increasing the burden on an already vulnerable patient population, and introducing the further risk of infection. To provide insight into the risks of early intervention, we investigate the relationship between initial device implantation before the age of 3 and the rate of unplanned reoperation. METHODS: A retrospective review was performed of all patients at a single institution who had undergone VEPTR insertion for EOS with at least a 2-year follow-up from 2007 to 2016. Patients were stratified into the case-cohort (0 to 2 y of age) or the comparison cohort (3 to 10 y of age) based on age at the time of device implantation. Multivariate regression accounting for age and scoliosis etiology was performed to identify factors predictive of unplanned reoperation. RESULTS: A total of 137 of 185 patients treated with VEPTR were identified with 76 (56%) undergoing at least 1 unplanned reoperation during the study time period. There were 68 and 69 patients in the age 0- to 2-year and 3- to 10-year cohorts, respectively. Patients aged 0 to 2 years underwent a higher number of total procedures compared with those aged 3 to 10 (13.1±6.5 vs. 10.6±4.8, P=0.032). A significant difference was found in the rate of unplanned reoperation between the 2 cohorts with 44 (65%) patients aged 0 to 2 and 32 (46%) patients aged 3 to 10 undergoing at least 1 unplanned reoperation (P=0.031). Binary logistic multivariate regression accounting for age and scoliosis etiology demonstrated that patients aged 0 to 2 had a significantly greater odds of undergoing an unplanned reoperation (odds ratio=3.050; 95% confidence interval: 1.285-7.241; P=0.011) compared with patients aged 3 to 10 years. CONCLUSION: Overall, EOS patients aged 0 to 2 at initial VEPTR implantation are up to 3 times higher risk of undergoing an unplanned reoperation compared with those aged 3 to 10. LEVEL OF EVIDENCE: Level III.

A Highly Prevalent and Pervasive Densovirus Discovered among Sea Stars from the North American Atlantic Coast.

The etiology of sea star wasting syndrome is hypothesized to be caused by a densovirus, sea star-associated densovirus (SSaDV), that has previously been reported on the Pacific and Atlantic Coasts of the United States. In this study, we reevaluated the presence of SSaDV among sea stars from the North American Atlantic Coast and in doing so discovered a novel densovirus that we have named Asterias forbesi-associated densovirus (AfaDV), which shares 78% nucleotide pairwise identity with SSaDV. In contrast to previous studies, SSaDV was not detected in sea stars from the North American Atlantic Coast. Using a variety of PCR-based techniques, we investigated the tissue tropism, host specificity, and prevalence of AfaDV among populations of sea stars at five locations along the Atlantic Coast. AfaDV was detected in three sea star species (Asterias forbesi, Asterias rubens, and Henricia sp.) found in this region and was highly prevalent (>80% of individuals tested; n = 134), among sampled populations. AfaDV was detected in the body wall, gonads, and pyloric caeca (digestive gland) of specimens but was not detected in their coelomic fluid. A significant difference in viral load (copies mg-1) was found between tissue types, with the pyloric caeca having the highest viral loads. Further investigation of Asterias forbesi gonad tissue found germ line cells (oocytes) to be virus positive, suggesting a potential route of vertical transmission. Taken together, these observations show that the presence of AfaDV is not an indicator of sea star wasting syndrome because AfaDV is a common constituent of these animals' microbiome, regardless of health.IMPORTANCE Sea star wasting syndrome is a disease primarily observed on the Pacific and Atlantic Coasts of North America that has significantly impacted sea star populations. The etiology of this disease is unknown, although it is hypothesized to be caused by a densovirus, SSaDV. However, previous studies have not found a correlation between SSaDV and sea star wasting syndrome on the North American Atlantic Coast. This study suggests that this observation may be explained by the presence of a genetically similar densovirus, AfaDV, that may have confounded previous studies. SSaDV was not present in sea stars screened in this study, and instead, AfaDV was commonly found in sea star populations across the New England region, with no apparent signs of disease. These results suggest that sea star densoviruses may be common constituents of the animals' microbiome, and the diversity and extent of these viruses among wild populations may be greater than previously recognized.

Association between timing of kyphoplasty and opioid prescribing risk after vertebral fracture.

OBJECTIVE: Approximately 550,000 Americans experience vertebral fracture annually, and most receive opioids to treat the resulting pain. Kyphoplasty of the fractured vertebra is a procedural alternative that may mitigate risks of even short-term opioid use. While reports of kyphoplasty's impact on pain scores are mixed, no large-scale data exist regarding opioid prescribing before and after the procedure. This study was conducted to determine whether timing of kyphoplasty following vertebral fracture is associated with duration or intensity of opioid prescribing. METHODS: This retrospective cohort study used 2001-2014 insurance claims data from a single, large private insurer in the US across multiple care settings. Patients were adults with vertebral fractures who were prescribed opioids and underwent balloon-assisted kyphoplasty within 4 months of fracture. Opioid overdose risk was stratified by prescribed average daily morphine milligram equivalents using CDC guidelines. Filled prescriptions and risk categories were evaluated at baseline and 90 days following kyphoplasty. RESULTS: Inclusion criteria were met by 7119 patients (median age 77 years, 71.7% female). Among included patients, 3505 (49.2%) were opioid naïve before fracture. Of these patients, 31.1% had new persistent opioid prescribing beyond 90 days after kyphoplasty, and multivariable logistic regression identified kyphoplasty after 8 weeks as a predictor (OR 1.34, 95% CI 1.02-1.76). For patients previously receiving opioids, kyphoplasty > 4 weeks after fracture was associated with persistently elevated prescribing risk (OR 1.84, 95% CI 1.23-2.74). CONCLUSIONS: New persistent opioid prescribing occurred in nearly one-third of patients undergoing kyphoplasty after vertebral fracture, although early treatment was associated with a reduction in this risk. For patients not naïve to opioids before fracture diagnosis, early kyphoplasty was associated with less persistent elevation of opioid overdose risk. Subsequent trials must compare opioid use by vertebral fracture patients treated via operative (kyphoplasty) and nonoperative (ongoing opioid) strategies before concluding that kyphoplasty lacks value, and early referral for kyphoplasty may be appropriate to avoid missing a window of efficacy.

Comparison of T1-S1 Spine Height of Postoperative Rib-based Implant Patients With Age-matched Peers.

BACKGROUND: Severe early-onset scoliosis leads to deficient spine height, thoracic growth inhibition, and ultimately pulmonary compromise. Rib-based growing instrumentation seeks to correct thoracic deformities, in part by correcting the spinal deformity, adding height, increasing thoracic volume, and allowing for continual spinal growth until maturity. However, the amount of growth in these patients relative to their peers is unknown. METHODS: Sixty patients who had undergone surgical intervention for the treatment of early-onset scoliosis were assessed via radiographic measurements of coronal T1-S1 height and major curve angle before implantation and again at most recent follow-up (minimum 2 years). T1-S1 measurements were then compared with age-matched peers to assess growth differences. Clinical information was examined for relevant parameters. RESULTS: The average age of our cohort at initial surgery and most recent follow-up was 4.4±3.8 and 10.0±4.4 years old, respectively. In this patient set, there was an average increase in T1-S1 height of 13.1±11.1 mm per year, with the majority of growth occurring in the first 2 years following implantation, and improvement in a major curve from 68±8 to 53±7 degrees. Overall, 77% of patients saw improvement in the major curve at most recent follow-up. Furthermore, a statistically significant greater percent of expected growth was seen in congenital compared with neuromuscular scoliosis (P<0.001). In addition, a weak negative correlation was observed between a number of surgical lengthenings and T1-S1 growth. CONCLUSIONS: Rib-based implant intervention has been shown to improve the major curve, but only improves growth potential to around 80% of expected growth. Scoliosis diagnosis type also influences growth rate potential, with congenital scoliosis patients being surgically treated earlier in life and having a growth rate approaching that of a healthy individual. LEVEL OF EVIDENCE: Level III-Case control.

Where Have All the Fractures Gone? The Epidemiology of Pediatric Fractures During the COVID-19 Pandemic.

BACKGROUND: During the COVID-19 pandemic, public health measures to encourage social distancing have been implemented, including cancellation of school and organized sports. A resulting change in pediatric fracture epidemiology is expected. This study examines the impact of the COVID-19 pandemic on fracture incidence and characteristics. METHODS: This is a retrospective cohort study comparing acute fractures presenting to a single level I pediatric trauma hospital during the COVID-19 pandemic with fractures during a prepandemic period at the same institution. The "pandemic" cohort was gathered from March 15 to April 15, 2020 and compared with a "prepandemic" cohort from the same time window in 2018 and 2019. RESULTS: In total, 1745 patients presenting with acute fractures were included. There was a significant decrease in the incidence of fractures presenting to our practice during the pandemic (22.5±9.1/d vs. 9.6±5.1/d, P<0.001). The presenting age for all fractures decreased during the pandemic (7.5±4.3 vs. 9.4±4.4 y, P<0.001) because of decreased fracture burden among adolescents. There were also a decrease in the number of fractures requiring surgery (2.2±1.8/d vs. 0.8±0.8/d, P<0.001). During the pandemic, there was an increase in the proportion of injuries occurring at home (57.8% vs. 32.5%, P<0.001) or on bicycles (18.3% vs. 8.2%, P<0.001), but a decrease in those related to sports (7.2% vs. 26.0%, P<0.001) or playgrounds (5.2% vs. 9.0%, P<0.001). There was no increase in time-to-presentation. Patients with distal radius torus fractures were more likely to receive a velcro splint during the pandemic (44.2% vs. 25.9%, P=0.010). CONCLUSIONS: Pediatric fracture volume has decreased 2.5-fold during the COVID-19 pandemic, partially because of cessation of organized sports and decreased playground use. In endemic regions, lower trauma volume may allow redeployment of orthopaedic surgeons and staff to other clinical arenas. Given the rising proportion of bicycling injuries, an emphasis on basic safety precautions could improve public health. An observed increase in the prescription of velcro splints for distal radius fractures highlights an opportunity for simplified patient care during the pandemic. LEVEL OF EVIDENCE: Level III.

Combinatorial lentiviral gene delivery of pro-oligodendrogenic factors for improving myelination of regenerating axons after spinal cord injury.

Spinal cord injury (SCI) results in paralysis below the injury and strategies are being developed that support axonal regrowth, yet recovery lags, in part, because many axons are not remyelinated. Herein, we investigated strategies to increase myelination of regenerating axons by overexpression of platelet-derived growth factor (PDGF)-AA and noggin either alone or in combination in a mouse SCI model. Noggin and PDGF-AA have been identified as factors that enhance recruitment and differentiation of endogenous progenitors to promote myelination. Lentivirus encoding for these factors was delivered from a multichannel bridge, which we have previously shown creates a permissive environment and supports robust axonal growth through channels. The combination of noggin+PDGF enhanced total myelination of regenerating axons relative to either factor alone, and importantly, enhanced functional recovery relative to the control condition. The increase in myelination was consistent with an increase in oligodendrocyte-derived myelin, which was also associated with a greater density of cells of an oligodendroglial lineage relative to each factor individually and control conditions. These results suggest enhanced myelination of regenerating axons by noggin+PDGF that act on oligodendrocyte-lineage cells post-SCI, which ultimately led to improved functional outcomes.

Safe Transportation in-Spica Following Surgical Treatment of Infantile DDH: Solutions and Threats.

BACKGROUND: Government regulations mandate appropriate vehicular restraints for children under 4 years of age. Patients treated for infantile developmental dysplasia of the hip (DDH) with spica casts often require special accommodations. Previous work suggests that car seat loaner programs may help achieve these goals while avoiding the need for costly ambulance transportation. The purpose of this study was to evaluate our center's experience with postdischarge transportation in a large population of DDH infants and identify future threats to our program. METHODS: We performed a retrospective review of patients 4 years or younger of age who underwent closed or open reduction for DDH at our center between 2011 and 2018. Only the initial surgery of staged procedures was included. Patient demographic factors were recorded, as were procedure type, final restraint used for postdischarge transportation, and any potential discharge delays secondary to transportation issues. Costs were compared amongst transportation options. RESULTS: Our cohort consisted of 130 patients (mean age, 1.4±0.9 y; 98 females) treated for DDH. In total 41 children (31.5%) underwent closed reduction procedures, whereas 89 patients (68.5%) underwent open reductions. After reduction, 62 (47.7%) received 2-legged spica casts and 68 (52.3%) received 1.5-legged casts. The most common restraint was a hospital-loaned Hippo car seat (73, 55.8%) followed by family-owned car seats (27, 20.8%). Eight patients (6.2%) experienced delays in discharge while waiting for adequate restraints, 6 patients (4.6%) were transported by ambulance, and 4 patients (3.1%) left against medical advice with inadequate restraints. CONCLUSIONS: Following surgical treatment of DDH, over 50% of patients with a spica cast were discharged using our center's car seat loaner program. However, availability and cost can present barriers for patients, with 4.6% of patients still being transported home by ambulance and 3.1% with inadequate restraints against medical advice. Costs of car seats are significant both for patients' families intending to purchase them, as well as for hospitals maintaining loaner programs and replacing used/lost seats. Moving forward, the recent cessation of production of the most common "spica car seat" threatens the longevity of existing loaner programs and calls renewed attention to the issue of safe transportation in-spica from providers and car-seat manufacturers alike. LEVEL OF EVIDENCE: Level III.

Quantifying cellular protrusion in alginate capsules with covalently crosslinked shells.

This work describes viability and distribution of INS-1E beta cells in shell-crosslinked alginate capsules, focussing on cells located near the capsule surface. Capsules were formed by air-shearing alginate suspensions of INS-1E cells into a gelling bath, and coating with poly-l-lysine (PLL) and 50% hydrolysed poly(methylvinylether-alt-maleic anhydride) to form crosslinked networks reinforcing the capsule surfaces. The percentage of cells at the capsule surface were determined using 2D and 3D confocal colocalization mapping. Encapsulated INS-1E cells showed high cell viability and progressive cell clustering out to six weeks. About 30% of cells were initially colocated with the 20 micrometer thick alginate-PLL-PMM50 shell, with 7% of cells protruded at the capsule surfaces, both reflecting random cell distributions. Protruding cells may cause cell-based immune responses, weaken capsules, and potentially result in cell escape from the capsules. The data shown indicate that reinforcing capsules with crosslinked shells may assist in preventing cell exposure and escape.

Effects of Lipid Tethering in Extremophile-Inspired Membranes on H(+)/OH(-) Flux at Room Temperature.

This work explores the proton/hydroxide permeability (PH+/OH-) of membranes that were made of synthetic extremophile-inspired phospholipids with systematically varied structural elements. A fluorescence-based permeability assay was optimized to determine the effects on the PH+/OH- through liposome membranes with variations in the following lipid attributes: transmembrane tethering, tether length, and the presence of isoprenoid methyl groups on one or both lipid tails. All permeability assays were performed in the presence of a low concentration of valinomycin (10 nM) to prevent buildup of a membrane potential without artificially increasing the measured PH+/OH-. Surprisingly, the presence of a transmembrane tether did not impact PH+/OH- at room temperature. Among tethered lipid monolayers, PH+/OH- increased with increasing tether length if the number of carbons in the untethered acyl tail was constant. Untethered lipids with two isoprenoid methyl tails led to lower PH+/OH- values than lipids with only one or no isoprenoid tails. Molecular dynamics simulations revealed a strong positive correlation between the probability of observing water molecules in the hydrophobic core of these lipid membranes and their proton permeability. We propose that water penetration as revealed by molecular dynamics may provide a general strategy for predicting proton permeability through various lipid membranes without the need for experimentation.

Lessons Learned from the Sea Star Wasting Disease Investigation.

Marine invertebrate mass mortality events (MMEs) threaten biodiversity and have the potential to catastrophically alter ecosystem structure. A proximal question around acute MMEs is their etiologies and/or environmental drivers. Establishing a robust cause of mortality is challenging in marine habitats due to the complexity of the interactions among species and the free dispersal of microorganisms from surrounding waters to metazoan microbiomes. The 2013-2014 sea star wasting disease (SSWD) MME in the northeast Pacific Ocean highlights the difficulty in establishing responsible agents. In less than a year of scientific investigation, investigators identified a candidate agent and provided at the time convincing data of pathogenic and transmissible disease. However, later investigation failed to support the initial results, and critical retrospective analyses of experimental procedures and reinterpretation of early findings disbanded any candidate agent. Despite the circuitous path that the investigation and understanding of SSWD have taken, lessons learned from the initial investigation-improving on approaches that led to misinterpretation-have been successfully applied to the 2022 Diadema antillarum investigation. In this review, we outline the history of the initial SSWD investigation, examine how early exploration led to spurious interpretations, summarize the lessons learned, provide recommendations for future work in other systems, and examine potential links between the SSWD event and the Diadema antillarum MME.

Perioperative Infection Prophylaxis with Vancomycin is a Significant Risk Factor for Deep Surgical Site Infection in Spine Surgery.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: The purpose of this study was to compare the efficacy of cefazolin versus vancomycin for perioperative infection prophylaxis. SUMMARY OF BACKGROUND DATA: The relative efficacy of cefazolin alternatives for perioperative infection prophylaxis is poorly understood. METHODS: This study was a single-center multi-surgeon retrospective review of all patients undergoing primary spine surgery from an institutional registry. Postoperative infection was defined by the combination of three criteria: irrigation and debridement within 3 months of the index procedure, clinical suspicion for infection, and positive intraoperative cultures. Microbiology records for all infections were reviewed to assess the infectious organism and organism susceptibilities. Univariate and multivariate analyses were performed. RESULTS: A total of 10,122 patients met inclusion criteria. The overall incidence of infection was 0.78%, with an incidence of 0.73% in patients who received cefazolin and 2.03% in patients who received vancomycin (OR 2.83, 95% CI 1.35-5.91, P-0.004). Use of IV vancomycin (OR 2.83, 95% CI 1.35-5.91, P=0.006), BMI (MD 1.56, 95% CI 0.32-2.79, P=0.014), presence of a fusion (OR 1.62, 95% CI 1.04-2.52, P=0.033), and operative time (MD 42.04, 95% CI 16.88-67.21, P=0.001) were significant risk factors in the univariate analysis. In the multivariate analysis, only non-cefazolin antibiotics (OR 2.48, 95% CI 1.18-5.22, P=0.017) and BMI (MD 1.56, 95% CI 0.32-2.79, P=0.026) remained significant independent risk factors. Neither IV antibiotic regimen nor topical vancomycin significantly impacted Gram type, organism type, or antibiotic resistance (P>0.05). The most common reason for antibiosis with vancomycin was a penicillin allergy (75.0%). CONCLUSIONS: Prophylactic antibiosis with IV vancomycin leads to a 2.5-times higher risk of infection compared to IV cefazolin in primary spine surgery. We recommend the routine use of IV cefazolin for infection prophylaxis, and caution against the elective use of alternative regimens like IV vancomycin unless clinically warranted.