Temporal Diffusion Ratio (TDR) for imaging restricted diffusion: Optimisation and pre-clinical demonstration.

Temporal Diffusion Ratio (TDR) is a recently proposed dMRI technique (Dell'Acqua et al., proc. ISMRM 2019) which provides contrast between areas with restricted diffusion and areas either without restricted diffusion or with length scales too small for characterisation. Hence, it has a potential for informing on pore sizes, in particular the presence of large axon diameters or other cellular structures. TDR employs the signal from two dMRI acquisitions obtained with the same, large, b-value but with different diffusion gradient waveforms. TDR is advantageous as it employs standard acquisition sequences, does not make any assumptions on the underlying tissue structure and does not require any model fitting, avoiding issues related to model degeneracy. This work for the first time introduces and optimises the TDR method in simulation for a range of different tissues and scanner constraints and validates it in a pre-clinical demonstration. We consider both substrates containing cylinders and spherical structures, representing cell soma in tissue. Our results show that contrasting an acquisition with short gradient duration, short diffusion time and high gradient strength with an acquisition with long gradient duration, long diffusion time and low gradient strength, maximises the TDR contrast for a wide range of pore configurations. Additionally, in the presence of Rician noise, computing TDR from a subset (50% or fewer) of the acquired diffusion gradients rather than the entire shell as proposed originally further improves the contrast. In the last part of the work the results are demonstrated experimentally on rat spinal cord. In line with simulations, the experimental data shows that optimised TDR improves the contrast compared to non-optimised TDR. Furthermore, we find a strong correlation between TDR and histology measurements of axon diameter. In conclusion, we find that TDR has great potential and is a very promising alternative (or potentially complement) to model-based approaches for informing on pore sizes and restricted diffusion in general.

Factors that Influence Acquisition of Lower Extremity Braces in the Pediatric Orthopaedic Population.

BACKGROUND: Lower extremity brace-wear compliance has been studied in pediatrics, but failure to acquire a prescribed brace has not been included. The purpose of this study was to evaluate brace acquisition as a component of brace-wear compliance. METHODS: Records of patients (0 to 21 y) prescribed lower extremity braces from 2017 to 2019 were reviewed. Diagnoses included cerebral palsy, spina bifida, short Achilles tendon, clubfoot, and other. Brace type was categorized as clubfoot foot abduction orthosis, ankle-foot orthosis, knee, hip, or custom/other braces. Brace prescription and acquisition dates were recorded. Insurance was classified as government, private, or uninsured. Patient demographics included age, sex, race, and calculated area deprivation index. RESULTS: Of the 1176 prescribed lower extremity braces, 1094 (93%) were acquired while 82 (7%) were not. The odds ratios (OR) of failure to acquire a prescribed brace in Black and Hispanic patients were 1.64 and 2.71 times that in White patients, respectively (95% confidence interval: 1.01-2.71, P=0.045; 1.23-5.6, P=0.015); in patients without insurance, the OR was 8.48 times that in privately insured patients (95% confidence interval: 1.93-31.1, P=0.007). The ORs of failure to acquire were 2.12 (P=0.003) in patients 4 years or more versus 0 to 3 years, 4.17 (P<0.0001) in cerebral palsy versus clubfoot, and 4.12 (P=0.01) in short Achilles tendon versus clubfoot. There was no significant association between sex or area deprivation index and failure of brace acquisition. CONCLUSIONS: In our cohort, 7% of prescribed braces were not acquired. Black or Hispanic race, lack of insurance, and older age were associated with failure to acquire prescribed braces. Braces prescribed for clubfoot were acquired more often than for cerebral palsy or short Achilles tendon. Brace-wear compliance is an established factor in treatment success and recurrence. This study identified risk factors for failed brace acquisition, a critical step for improving compliance. These results may help effect changes in the current system that may lead to more compliance with brace wear. LEVEL OF EVIDENCE: Level III-retrospective cohort study.

Estimating the annual dengue force of infection from the age of reporting primary infections across urban centres in endemic countries.

BACKGROUND: Stratifying dengue risk within endemic countries is crucial for allocating limited control interventions. Current methods of monitoring dengue transmission intensity rely on potentially inaccurate incidence estimates. We investigated whether incidence or alternate metrics obtained from standard, or laboratory, surveillance operations represent accurate surrogate indicators of the burden of dengue and can be used to monitor the force of infection (FOI) across urban centres. METHODS: Among those who reported and resided in 13 cities across the Philippines, we collected epidemiological data from all dengue case reports between 2014 and 2017 (N 80,043) and additional laboratory data from a cross-section of sampled case reports (N 11,906) between 2014 and 2018. At the city level, we estimated the aggregated annual FOI from age-accumulated IgG among the non-dengue reporting population using catalytic modelling. We compared city-aggregated FOI estimates to aggregated incidence and the mean age of clinically and laboratory diagnosed dengue cases using Pearson's Correlation coefficient and generated predicted FOI estimates using regression modelling. RESULTS: We observed spatial heterogeneity in the dengue average annual FOI across sampled cities, ranging from 0.054 [0.036-0.081] to 0.249 [0.223-0.279]. Compared to FOI estimates, the mean age of primary dengue infections had the strongest association (ρ -0.848, p value<0.001) followed by the mean age of those reporting with warning signs (ρ -0.642, p value 0.018). Using regression modelling, we estimated the predicted annual dengue FOI across urban centres from the age of those reporting with primary infections and revealed prominent spatio-temporal heterogeneity in transmission intensity. CONCLUSIONS: We show the mean age of those reporting with their first dengue infection or those reporting with warning signs of dengue represent superior indicators of the dengue FOI compared to crude incidence across urban centres. Our work provides a framework for national dengue surveillance to routinely monitor transmission and target control interventions to populations most in need.

Immune responses to malaria pre-erythrocytic stages: Implications for vaccine development.

Radiation-attenuated sporozoites induce sterilizing immunity and remain the 'gold standard' for malaria vaccine development. Despite practical challenges in translating these whole sporozoite vaccines to large-scale intervention programmes, they have provided an excellent platform to dissect the immune responses to malaria pre-erythrocytic (PE) stages, comprising both sporozoites and exoerythrocytic forms. Investigations in rodent models have provided insights that led to the clinical translation of various vaccine candidates-including RTS,S/AS01, the most advanced candidate currently in a trial implementation programme in three African countries. With advances in immunology, transcriptomics and proteomics, and application of lessons from past failures, an effective, long-lasting and wide-scale malaria PE vaccine remains feasible. This review underscores the progress in PE vaccine development, focusing on our understanding of host-parasite immunological crosstalk in the tissue environments of the skin and the liver. We highlight possible gaps in the current knowledge of PE immunity that can impact future malaria vaccine development efforts.

Intraobserver and Interobserver Reliability of the Peritubercle Lucency Sign in Slipped Capital Femoral Epiphysis.

BACKGROUND: An area of enlargement of the metaphyseal socket around the epiphyseal tubercle, termed the peritubercle lucency sign, has recently been introduced as a possible predictor of contralateral slipped capital femoral epiphysis in patients with previous unilateral slipped capital femoral epiphysis. This study aimed to assess intraobserver and interobserver reliability for detecting the presence or absence of the peritubercle lucency sign. METHODS: Thirty-five radiographs were presented to 6 fellowship-trained pediatric orthopaedic surgeons on 2 separate occasions 30 days apart, ensuring that the images were shown in a different order on the second exposure. Both times the reviewers recorded whether the peritubercle lucency sign was present or absent in each of the radiographs. Statistical analysis was performed to determine the intraobserver and interobserver reliability. RESULTS: In the intraobserver analysis, percent agreement between the first and second time the radiographs were reviewed varied between 62.9% and 85.7%, for an average intraobserver agreement of 74.8%. κ values for the 6 reviewers varied between 0.34 and 0.716, with an average intraobserver κ value of 0.508. The interobserver percent agreement was 40.0% for the first time the radiographs were reviewed, 42.9% the second time, and the overall interobserver percent agreement was 29%. The interobserver κ value was 0.44 the first time the radiographs were reviewed, 0.45 the second time, and the overall interobserver κ value was 0.45. DISCUSSION: On the basis of our findings, the peritubercle lucency has modest intraobserver and interobserver reliability at best and should be used with other currently used factors, such as age, presence of endocrinopathy, status of triradiate cartilage, posterior sloping angle, and modified Oxford score, in determining the need for prophylactic pinning. Further refinement of the definition of the peritubercle lucency sign may be needed to improve agreement and reliability of the sign. LEVEL OF EVIDENCE: Level III-prognostic study.

A serological framework to investigate acute primary and post-primary dengue cases reporting across the Philippines.

BACKGROUND: In dengue-endemic countries, targeting limited control interventions to populations at risk of severe disease could enable increased efficiency. Individuals who have had their first (primary) dengue infection are at risk of developing more severe secondary disease, thus could be targeted for disease prevention. Currently, there is no reliable algorithm for determining primary and post-primary (infection with more than one flavivirus) status from a single serum sample. In this study, we developed and validated an immune status algorithm using single acute serum samples from reporting patients and investigated dengue immuno-epidemiological patterns across the Philippines. METHODS: During 2015/2016, a cross-sectional sample of 10,137 dengue case reports provided serum for molecular (anti-DENV PCR) and serological (anti-DENV IgM/G capture ELISA) assay. Using mixture modelling, we re-assessed IgM/G seroprevalence and estimated functional, disease day-specific, IgG:IgM ratios that categorised the reporting population as negative, historical, primary and post-primary for dengue. We validated our algorithm against WHO gold standard criteria and investigated cross-reactivity with Zika by assaying a random subset for anti-ZIKV IgM and IgG. Lastly, using our algorithm, we explored immuno-epidemiological patterns of dengue across the Philippines. RESULTS: Our modelled IgM and IgG seroprevalence thresholds were lower than kit-provided thresholds. Individuals anti-DENV PCR+ or IgM+ were classified as active dengue infections (83.1%, 6998/8425). IgG- and IgG+ active dengue infections on disease days 1 and 2 were categorised as primary and post-primary, respectively, while those on disease days 3 to 5 with IgG:IgM ratios below and above 0.45 were classified as primary and post-primary, respectively. A significant proportion of post-primary dengue infections had elevated anti-ZIKV IgG inferring previous Zika exposure. Our algorithm achieved 90.5% serological agreement with WHO standard practice. Post-primary dengue infections were more likely to be older and present with severe symptoms. Finally, we identified a spatio-temporal cluster of primary dengue case reporting in northern Luzon during 2016. CONCLUSIONS: Our dengue immune status algorithm can equip surveillance operations with the means to target dengue control efforts. The algorithm accurately identified primary dengue infections who are at risk of future severe disease.

The Role of Computed Tomography and Magnetic Resonance Imaging in the Diagnosis of Pediatric Thoracolumbar Compression Fractures.

BACKGROUND: Because of concerns about radiation exposure, some centers consider magnetic resonance imaging (MRIs) the preferred imaging modality for pediatric thoracic and/or lumbar compression fractures. The purpose of this study was to evaluate the sensitivity of computed tomography (CT) and MRI in diagnosing thoracolumbar compression fractures and the utility of MRI in their management. METHODS: Retrospective review identified 52 patients aged 0 to 18 years with 191 thoracic and/or lumbar compression fractures who had both CT and MRI during the initial trauma evaluation. The decision to perform CT and/or MRI was made by the attending pediatric spine surgeon. In all cases the CT scan was performed before the MRI. All imaging studies were reviewed by a board-certified pediatric radiologist and attending pediatric spine surgeon. RESULTS: Only 10 patients (19%) had a single-level injury. Of 42 with multiple compression fractures, 34 (81%) had fractures in contiguous levels, and 8 had noncontiguous injuries. Comparing CT and MRI, there was complete agreement in the number and distribution of fractures in 23 patients (44%). MRI identified additional levels of fracture in 15 patients (29%); 14 (27%) had fewer levels fractured on MRI than CT. Only one patient (2%) had fractures seen on MRI after a normal CT scan. Complete correlation between CT and MRI was seen in 59% (17/29) of patients aged 11 to 18 years, compared with 26% (6/23) of patients younger than 11. CONCLUSIONS: In pediatric patients with mild thoracic or lumbar compression fracture(s), CT scan demonstrates a high sensitivity in determining the presence or absence of a fracture compared with MRI. Although some variability exists between the 2 modalities in the exact number of spinal levels involved, the definitive treatment and outcome were not changed by the addition of MRI. The information that may be obtained from an MRI must be weighed against the increased time and expense of the study, as well as the risks associated with sedation when necessary. LEVEL OF EVIDENCE: Level II-diagnostic study.

Pediatric Patients with Spondylolysis Have High Rates of Vitamin-D Deficiency.

The objective of this study was to document the 25-hydroxyvitamin D status of patients with a confirmed diagnosis of spondylolysis to determine if these patients have increased rates of vitamin D deficiency. After confirming the diagnosis of spondylolysis, patients were prospectively enrolled in this study. A total of 39 patients (30 male, 9 female) with a mean age of 14.9 years and a mean BMI of 22.9 had vitamin D levels drawn after imaging confirmed the diagnosis of spondylolysis. The mean 25-hydroxyvitamin D level was 26 ng/ml. Only 9 patients (23.1%) were considered to have normal vitamin D levels > 32 ng/ml. An additional 22 patients (56.4%) had insufficient values of 20 to 32 ng/ml, and 8 patients (20.5%) had vitamin D deficiency with values <20 ng/ml. Pediatric patients presenting with spondylolysis, regardless of race or age, have high rates of 25-hydroxyvitamin D deficiency. (Journal of Surgical Orthopaedic Advances 28(4):257-259, 2019).

Biomechanical analysis of spino-pelvic postural configurations in spondylolysis subjected to various sport-related dynamic loading conditions.

PURPOSE: To study the risks of spondylolysis due to extrinsic loading conditions related to sports activities and intrinsic spino-pelvic postural parameters [pelvic incidence (PI) and sacral slope (SS)]. METHODS: A comprehensive osseo-disco-ligamentous L4-S1 finite element model was built for three cases with spondylolysis representing three different spino-pelvic angular configurations (SS = 32°, 47°, 59° and PI = 49°, 58°, 72°, respectively). After simulating the standing posture, 16 dynamic loading conditions were computationally tested for each configuration by combining four sport-related loads (compression, sagittal and lateral bending and axial torque). For each simulation, the Von Mises stress, L5-S1 facet contact force and resultant internal loads at the sacral endplate were computed. Significant effects were determined with an ANOVA. RESULTS: The maximal stress and volume of cancellous bone in the pars with stress higher than 75% of the ultimate stress were higher with 900 N simulated compression (2.2 MPa and 145 mm3) compared to only the body weight (1.36 MPa and 20.9 mm3) (p < 0.001). Combined compression with 10 Nm of flexion and an axial torque of 6 Nm generated the highest stress conditions (up to 2.7 MPa), and L5-S1 facet contact force (up to 430 N). The maximal stress was on average 17% higher for the case with the highest SS compared to the one with lowest SS for the 16 tested conditions (p = 0.0028). CONCLUSIONS: Combined flexion and axial rotation with compression generated the highest stress conditions related to risks of spondylolysis. The stress conditions intensify in patients with higher PI and SS. These slides can be retrieved under Electronic Supplementary Material.

Adolescent Spondylolysis: Management and Return to Play.

The most common causes of low back pain in adolescents are spondylolysis and spondylolisthesis. Mechanical factors combined with rapid growth during adolescence place stress on the spine and can result in a stress fracture. Sports that require athletes to repeatedly place the spine in hyperextension may exacerbate both spondylolysis and spondylolisthesis. Many adolescent athletes with spondylolysis or low-grade spondylolisthesis have minimal symptoms and require no treatment or alteration in activity, including sports activity. For adolescents with spondylolysis or low-grade spondylolisthesis who have symptoms, nonsurgical treatment with activity restrictions and a structured rehabilitation program can help in return to most sports. Surgical treatment may be required for patients who have symptoms that are unresponsive to nonsurgical treatment and patients who have grade III or grade IV spondylolisthesis. Treatment and return to competitive sports must be individualized based on the severity and symptoms of the disease in each patient.

Concussion in Sports: What Do Orthopaedic Surgeons Need to Know?

A concussion is a relatively common sports-related injury that affects athletes of all ages. Although not expected to replace sports medicine physicians and neurologists with regard to the management of concussions, orthopaedic surgeons, particularly those who are fellowship-trained in sports medicine, must have a current knowledge base of what a concussion is, how a concussion is diagnosed, and how a concussion should be managed. Orthopaedic surgeons should understand the pathophysiology, assessment, and management of concussion so that they have a basic comprehension of this injury that is at the forefront of the academic literature and North American media. This understanding will prepare orthopaedic surgeons to work in concert with and assist sports medicine physicians, athletic trainers, and physical therapists in providing comprehensive care for athletes with a concussion.

Update in Pediatric Musculoskeletal Infections: When It Is, When It Isn't, and What to Do.

Musculoskeletal infections, including osteomyelitis, septic arthritis, and pyomyositis, are a substantial cause of morbidity in children and adolescents. The increased virulence of infectious agents and the increased prevalence of antimicrobial-resistant pathogens, particularly methicillin-resistant Staphylococcus aureus, have resulted in a more complicated clinical course for diagnosis and management, which is evidenced by an increased length of hospital stays, incidence of complications, and number of surgical interventions. Musculoskeletal infections are a challenge for surgeons because they vary substantially in their presentation and in their required treatment, which is based on the causative organism, the location of the infection, and the age of the patient. The necessity for a prompt diagnosis is complicated by several diseases that may mimic musculoskeletal infection, including transient synovitis, autoimmune arthritis, and tumors. Recent innovations in diagnosis and management have provided surgeons with new options to differentiate musculoskeletal infections from these rapidly evolving disease pathologies. As diagnostic and treatment modalities improve, collaboration among surgeons from multiple disciplines is required to develop evidence-based clinical practice guidelines that minimize the effect of musculoskeletal infection and optimize clinical outcomes for patients.

Use of Vertical Expandable Prosthetic Titanium Rib (VEPTR) in the Treatment of Congenital Scoliosis Without Fused Ribs.

BACKGROUND: Although the vertical expandable prosthetic titanium rib (VEPTR) has been shown to be useful in treating congenital scoliosis (CS) with fused ribs, no studies to date have specifically evaluated the efficacy of VEPTR in the treatment of CS without fused ribs. The purpose of this study was to determine the effectiveness of VEPTR in sagittal/coronal curve correction and spine growth and compare its complication rate to the use of VEPTR in other conditions and to other treatment methods used for CS. METHODS: A multicenter database was queried for patients with CS without fused ribs treated with VEPTR. Anteroposterior (AP) and lateral radiographs were used to measure parameters at 3 timepoints (preoperative, immediate postoperative, and latest follow-up): coronal Cobb angle, sagittal kyphosis, and thoracic and lumbar spine heights. Clinical data included age, time to follow-up, and complications. RESULTS: Twenty-five patients (13 females, 12 males) were identified. The average age at implantation was 5.7 years, with an average follow-up of 50 months. Several parameters improved from preoperative to latest follow-up: coronal Cobb angle (69 to 54 degrees, P<0.0001), thoracic spine height (T1-T12) in the AP (13.3 to 15.9 cm, P<0.0001) and lateral (14.8 to 17.4 cm, P=0.0024) planes, and lumbar spine height (L1-S1) in the AP (8.8 to 11.4 cm, P<0.0001) and lateral (9.9 to 11.9 cm, P=0.0002) planes. Kyphosis increased over the study period (36 to 41 degrees, P=0.6). Fifteen patients (60%) had 41 complications (average 2.75; range, 1 to 12). Twenty-eight complications (68%) were device-related, and 13 (32%) were disease-related. The most common complications were infection, wound dehiscence, and device migration. Six complications (15%) altered the course of treatment. Thoracic spine height increased 79% of expected growth. CONCLUSION: VEPTR is an effective treatment for patients with CS without fused ribs, as evidenced by improved radiographic parameters and increased spinal height, with a complication rate which is high but similar to other methods of treatment. LEVEL OF EVIDENCE: Level IV-case series.

Epidemiology of Pediatric Fractures Presenting to Emergency Departments in the United States.

BACKGROUND: Fractures in children are an important public health issue and a frequent cause of emergency room visits. The purpose of this descriptive epidemiological study was to identify the most frequent pediatric fractures per 1000 population at risk in the United States using the 2010 National Electronic Injury Surveillance System (NEISS) database and 2010 US Census information. METHODS: The NEISS database was queried for all fractures in 2010 in children between the ages of 0 and 19 years. The NEISS national estimates were compared with the 2010 US Census data to extrapolate national occurrence rates. RESULTS: The annual occurrence of fractures increased from ages 0 to 14, peaking in the 10 to 14 age range (15.23 per 1000 children). The annual occurrence rate for the entire pediatric population (0 to 19 y) was 9.47 per 1000 children. Fractures of the lower arm (forearm) were the most common among the entire study population, accounting for 17.8% of all fractures, whereas finger and wrist fractures were the second and third most common, respectively. Finger and hand fractures were most common for age groups 10 to 14 and 15 to 19 years, respectively. The overall risk of a fracture occurring throughout childhood and adolescence was 180 per 1000 children, or just under 1 in every 5 children. CONCLUSIONS: Pediatric fractures represent a significant proportion of pediatric emergency department visits in the United States. Children between 10 and 14 years of age have the highest risk of having fractures. Overall, forearm fractures were the most common pediatric fractures. Most pediatric fractures can be treated on outpatient basis, with only 1 of 18 fractures requiring hospitalization or observation. LEVEL OF EVIDENCE: Level III-Retrospective comparative study.

Outcomes and Complications of Tibial Tubercle Fractures in Pediatric Patients: A Systematic Review of the Literature.

BACKGROUND: Systematic review of the literature was done to determine (1) the frequency and type of associated injuries, (2) frequency of concomitant Osgood-Schlatter disease, (3) methods of treatment, (4) functional and radiologic outcomes according to fracture type, and (5) complications of tibial tubercle fractures in pediatric patients. METHODS: A systematic review of the English literature from 1970 to 2013 included 23 eligible articles reporting 336 fractures with a mean follow-up of 33.56 months (range, 5.7 to 115 mo). Fractures were classified by a comprehensive system that included characteristics of previous systems. Clinical outcomes were assessed by a qualitative scale (excellent/fair/poor), the rate of return to preinjury activity, and knee range of motion. Rate of fracture healing, associated injuries (patellar/quadriceps tendon avulsion and meniscal tears), compartment syndrome, and complications were also recorded. RESULTS: Mean age at surgery was 14.6 years and the most common fracture reported was type III (50.6%). The overall associated injury rate was 4.1%, most common in type III fractures (4.7%). Compartment syndrome was present in 3.57% of cases. Open reduction and internal fixation were done in 98% of surgical cases. Rates of return to preinjury activity and knee range of motion were 98%, regardless of the type of fracture. Fracture consolidation was achieved in 99.4% of cases. Overall complication rate was 28.3%; removal of an implant because of bursitis (55.8%) was most common. Tenderness/prominence (17.9%) and refracture (6.3%) were also common. CONCLUSIONS: Treatment of tibial tubercle fractures in adolescents produced good clinical and radiologic results regardless of fracture type, which was more related to potential complications. Fractures with intra-articular involvement tended to present with more associated injuries and to have fair functional outcomes, suggesting that advanced imaging may be justified with these fractures. Complications could be more common than expected without a significant effect on final outcome. Finally, there is a need for longer follow-up to determine long-term outcomes. LEVEL OF EVIDENCE: Level III-systematic review of level III/IV studies.

Gunshot-associated Fractures in Children and Adolescents Treated at Two Level 1 Pediatric Trauma Centers.

INTRODUCTION: Gunshot injuries are a potentially significant cause of morbidity and mortality in the pediatric population. The objective of this study was to evaluate the epidemiology, fracture locations, associated injuries, types of treatment, and complications of gunshot-associated fractures in children and adolescents treated at two level 1 trauma centers. METHODS: The clinical and radiographic records of all children and adolescents who had a gunshot-associated fracture treated at 1 of 2 level 1 pediatric trauma centers between January, 2005, and April, 2013, were reviewed. The following characteristics were recorded: patient age and sex, type of weapon, fracture location, presence of neurovascular injury or other associated injuries, antibiotic treatment, method of stabilization, duration of hospital stay, complications, and need for subsequent procedures. RESULTS: Forty-nine patients with 58 fractures were identified; 9 patients had multiple fractures. The 41 males and 8 females had an average age of 12.2 years (range, 1 to 18 y). The tibia and femur were the most common sites of fracture (19% each), followed by the small bones of foot (4%) and the fibula (4%). Most of the fractures (71%) were treated nonoperatively. Nearly half (47%) of the patients had additional injuries, including abdominal or genitourinary injuries, neuropraxia or nerve injuries, and vascular injuries. Two patients (4%) developed infections (1 superficial and 1 deep) that required multiple irrigation and debridement procedures. Three patients developed compartment syndrome, and 4 patients had vascular injuries requiring repair. Nearly a third of patients (35%) had fractures or complications that required additional operative procedures. CONCLUSIONS: This large retrospective study highlights the significant morbidity of fractures caused by gunshots. Although the overall infection rate was low and most of these fractures were successfully treated nonoperatively, many of the patients required an additional operative procedure and nearly half had additional nonorthopaedic injuries. This emphasizes the necessity of coordination among emergency, general surgeons, intensivist, and orthopaedic surgical teams. LEVEL OF EVIDENCE: Level IV­retrospective case series.

Changes in the Treatment of Pediatric Femoral Fractures: 15-Year Trends From United States Kids' Inpatient Database (KID) 1997 to 2012.

BACKGROUND: The options for treating femoral fractures in children and adolescents have evolved over the last 2 decades to include a variety of nonoperative and operative methods. The purpose of this study was to identify changes in the types of treatment for pediatric femoral fractures in the United States from 1997 to 2012. METHODS: From discharge estimates for 1997, 2000, 2003, 2006, 2009, and 2012 in the Kids' Inpatient Database, data were extracted using the International Classification of Diseases, 9th revision, and Clinical Modification for pediatric femoral fracture treatments. Patients included were 0 to 17 years old and were categorized into 5 age groups: younger than 1, 1 to 4, 5 to 9, 10 to 14, and 15 to 17 years. RESULTS: A total of 74,483 estimated discharges were recorded for pediatric patients with femoral fractures in the database for years 1997, 2000, 2003, 2006, 2009, and 2012. A total of 12,986 pediatric femoral fractures were estimated for 1997 and 9813 for 2012, which was statistically different (P<0.0001). Significantly fewer fractures were treated with closed reduction alone in 2012 than in 1997 in age groups 5 to 9, 10 to 14, and 15 to 17 years. Children aged 5 to 9 had more frequent open reduction and internal fixation in 2012 than in 1997, whereas adolescents aged 15 to 17 had less frequent open reduction and internal fixation in 2012 than in 1997. CONCLUSIONS: Although the number of femoral shaft fractures overall has decreased, the frequency of operative treatment has increased significantly in patients 5 to 9 years of age. Knowledge of these trends can guide educational efforts and resource allocation, but further study is necessary to determine procedure-specific (eg, nailing, plating, external fixation) trends and their clinical and economic impacts. LEVEL OF EVIDENCE: Level III-case series.

Use of magnetic resonance imaging in the evaluation of spondylolysis.

BACKGROUND: In early studies, magnetic resonance imaging (MRI) had low sensitivity and positive predictive value in the evaluation of the pars interarticularis pathology; however, more recent reports have suggested an expanded role for MRI. The purpose of the present study was to evaluate the effectiveness of MRI in the diagnosis of pars injuries and compare it to computed tomography (CT), which was used as the reference "gold standard" for the detection of fractures. METHODS: The radiographic and clinic data of 93 adolescents and young adults with a presumptive diagnosis of spondylolysis based upon history and clinic examination were reviewed. Only 26 patients who had MRI and CT images obtained within 30 days of each other were included. All images were reviewed by a fellowship-trained musculoskeletal radiologist and fellowship-trained pediatric orthopaedist. RESULTS: Overall, 39 individual pars lesions (stress reaction or fracture) were identified. MRI was effective in identifying 36 pars lesions. MRI identified 11 lesions in 9 patients with negative CT. Seven of these lesions were stress reactions (grade 1), whereas 4 were frank fractures. Three pars injuries were noted on CT while the MRI was negative. CONCLUSIONS: MRI is an effective method (92% sensitivity) for detecting pars injuries. It can detect stress reactions when a fracture is not visible on CT scan, allowing early treatment of these prelysis lesions. The 92% sensitivity of MRI is comparable with that of other diagnostic modalities such as bone scan, with the advantage of no radiation exposure. MRI should be strongly considered as the advanced imaging modality of choice in the evaluation of patients with suspected spondylolysis. LEVEL OF EVIDENCE: Level III-diagnostic study.

Subaxial cervical spine injuries in children and adolescents.

BACKGROUND: Limited data exist on pediatric subaxial cervical spine injuries. The goal of this study was to characterize the injuries and initial treatment of a large consecutive series of patients with injuries from C3 to C7. METHODS: Medical records and radiographs of consecutive patients admitted with cervical spine fractures and/or dislocations at a single level 1 pediatric trauma center from 2003 to 2013 were reviewed. Data abstracted included age, injury type and level, mechanism of injury, associated nonspine injuries, neurological status, length of hospitalization, and initial treatment. RESULTS: Fifty-one patients were grouped into 3 age ranges: infant, 0 to 3 years (2); youth, 4 to 12 years (13); and adolescent, 13 to 16 years (36). Isolated fractures were identified in both infants and accounted for most of injuries in youths (85%) and adolescents (86%). Single vertebra or single vertebral level injuries were present in 65% of patients, most commonly at C7 (36%) or C6 (29%). No correlation existed between cervical level injured and patient age. Multiple cervical spine injuries occurred in 1 infant, 3 youths, and 14 adolescents. Other concomitant thoracic and/or lumbar spine injuries were found in 1 infant and 3 adolescents. The most common mechanisms of injury were motor vehicle accidents (53%) and sports (14%). High-energy trauma was associated with higher rates of noncontiguous spinal injuries and associated nonspinal injuries, with a longer length of hospitalization. Neurological deficits were observed in 8 patients: 1 infant, 2 youths, and 5 adolescents, of which 5 resulted from high-energy trauma. One infant and all youth patients were treated nonoperatively; 26 adolescents (73%) were treated in a cervical collar or with observation, 1 was treated with halo-vest immobilization, and 9 had surgical treatment. CONCLUSIONS: Most subaxial cervical spine injuries in pediatric and adolescent patients are isolated fractures at C6 and C7. High-energy mechanisms are associated with noncontiguous spinal injuries and other nonspine injuries. Most patients can be treated in a cervical collar, but adolescent patients are more likely to require halo placement or surgical intervention. LEVEL OF EVIDENCE: Level IV-retrospective, diagnostic.

Does preoperative orientation and education alleviate anxiety in posterior spinal fusion patients? A prospective, randomized study.

BACKGROUND: A prospective, randomized study examined the effect of interventional preoperative education and orientation for scoliosis surgery (PEOSS) on anxiety levels of patients undergoing posterior spinal fusion (PSF). Secondary outcomes analyzed were caregiver anxiety, length of stay, morphine equivalent usage, and patient/caregiver satisfaction. METHODS: Patients undergoing PSF were randomly distributed into a control group (N=39) or interventional group (N=26). All subjects and caregivers completed the State (current)-Trait (typical) Anxiety Inventory (STAI) at different intervals: preoperative appointment, preoperative holding area, postoperative orthopaedic unit, and discharge. At discharge, patients and caregivers completed a satisfaction survey. RESULTS: Significantly higher state anxiety scores were found compared with baseline at all time intervals in both the control group and PEOSS group. The PEOSS group had higher state anxiety scores than the control group at the postoperative interval (P=0.024). There were no significant differences in the caregiver state anxiety scores between the groups at any time interval. Trait anxiety scores for both groups remained stable over time, establishing that the measurement tool accurately reflected baseline anxiety. No significant differences were found in length of stay or morphine equivalent use. Patient satisfaction scores were higher in the PEOSS group than in the control group (P=0.0005). CONCLUSIONS: PSF was associated with increased anxiety at all time intervals in adolescents in both groups. In the PEOSS group, PSF was associated with increased anxiety in the immediate postoperative period. Despite the increase in anxiety, patient satisfaction was higher in the intervention group. It is likely that patients need age-appropriate information and educational strategies to minimize anxiety during PSF. Further work is underway to study and develop more effective interventional strategies. LEVEL OF EVIDENCE: Level I study.