Ultrasound Secondary Signs for the Diagnosis of Pediatric Distal Forearm Fractures: A Diagnostic Study.

OBJECTIVE: To evaluate the diagnostic accuracy of ultrasound secondary signs of fractures in pediatric patients aged 5-15 y presenting to the emergency department with a clinically non-deformed distal forearm injury. METHODS: This diagnostic study was conducted in South East Queensland, Australia. Emergency clinicians performed point-of-care ultrasound on eligible patients and recorded secondary signs of fractures (pronator quadratus hematoma [PQH] sign, periosteal hematoma, visible angulation) or physeal fractures (fracture-to-physis distance [FPD], physis alteration). The reference standard was the final fracture diagnosis determined by expert panel. The primary outcome was the diagnostic accuracy of secondary signs for cortical breach and physeal fractures. Diagnostic statistics were reported for each relevant secondary sign. RESULTS: A total of 135 participants were enrolled. The expert panel diagnosed 48 "no" fracture, 52 "buckle" fracture and 35 "other" fracture. All "other" fractures were cortical breach fractures and included 15 Salter-Harris II fractures. The PQH sign demonstrated high sensitivity and moderate specificity to diagnose cortical breach fractures (91%, 95% Confidence Interval [CI] 78%-97% and 82%, 73%-88%). Poor sensitivity but high specificity was observed for the visible angulation and periosteal hematoma secondary signs. FPD <1cm showed perfect sensitivity and moderate specificity (100%, 80%-100% and 85%, 78%-90%) for diagnosis of Salter-Harris II fracture. Conversely, physis alteration showed poor sensitivity but excellent specificity (40%, 20%-64% and 99%, 95%-100%) for the diagnosis of Salter-Harris II fractures. CONCLUSION: Ultrasound secondary signs showed good diagnostic accuracy for both cortical breach fractures and Salter-Harris II fractures. Future research should consider optimal use of secondary signs to improve diagnostic accuracy.

Diagnostic Accuracy of Point-of-Care Ultrasound Versus Radiographic Imaging for Pediatric Distal Forearm Fractures: A Randomized Controlled Trial.

STUDY OBJECTIVE: In patients aged 5 to 15 years with a clinically nondeformed distal forearm injury presenting to the emergency department (ED), we examined whether point-of-care ultrasound or radiographic imaging had better diagnostic accuracy, with the reference diagnosis determined by an expert panel review. METHODS: This multicenter, open-label, diagnostic randomized controlled trial was conducted in South East Queensland, Australia. Eligible patients were randomized to receive initial imaging through point-of-care ultrasound performed by an ED clinician or radiograph. Images were defined as "no," "buckle," or "other" fracture by the treating clinician. The primary outcome was the diagnostic accuracy of the treating clinician's interpretation compared against the reference standard diagnosis, which was determined retrospectively by an expert panel consisting of an emergency physician, pediatric radiologist, and pediatric orthopedic surgeon, who reviewed all imaging and follow-up. RESULTS: Two-hundred and seventy participants were enrolled, with 135 randomized to each initial imaging modality. There were 132 (97.8%) and 112 (83.0%) correctly diagnosed participants by ED clinicians in the point-of-care ultrasound and radiograph groups, respectively (absolute difference [AD]=14.8%; 95% confidence interval [CI] 8.0% to 21.6%; P<.001). Point-of-care ultrasound had better accuracy for participants with "buckle" fractures (AD=18.5%; 95% CI 7.1% to 29.8%) and "other" fractures (AD=17.1%; 95% CI 2.7% to 31.6%). No clinically important fractures were missed in either group. CONCLUSION: In children and adolescents presenting to the ED with a clinically nondeformed distal forearm injury, clinician-performed (acquired and interpreted) point-of-care ultrasound more accurately identified the correct diagnosis than clinician-interpreted radiographic imaging.

Leg-Length and Alignment Changes in Children and Adolescents After Transphyseal Anterior Cruciate Ligament Reconstruction With Soft Tissue Graft: Results at 1-Year Follow-up.

Background: Growth disturbance to leg length or coronal plane alignment are important considerations in pediatric anterior cruciate ligament (ACL) reconstruction (ACLR). Purpose/Hypothesis: The purpose of this study was to investigate the lower limb alignment and leg length of pediatric patients preoperatively and at approximately 1 year after transphyseal ACLR. Our hypothesis was that there would be no significant change in leg-length discrepancy (LLD) or operated-side alignment at follow-up. Study Design: Case series; Level of evidence, 4. Methods: Data were extracted from the prospective Queensland Children's Hospital Pediatric ACL Injury Registry. Long-leg alignment radiographs were captured preoperatively and at an approximately 12-month postoperative follow-up. Radiographic measures included leg length, LLD (injured minus uninjured leg length), mechanical axis deviation (MAD), mechanical and anatomical lateral distal femoral angle (mLDFA and aLDFA, respectively), and medial proximal tibial angle. We evaluated the effect of time (annual vs baseline) on imaging measurements with analysis of covariance, using the covariates of age, sex, and body mass index. Results: Data were available for 104 patients, of whom 34 (33%) had >12 months of skeletal growth remaining based on skeletal age. At an average follow-up time of 14.5 months after ACLR, there were no significant differences in mean lower limb alignment or longitudinal growth compared with baseline. However, seven patients demonstrated clinically significant changes to their mechanical axis or LLD (>10 mm change). A subgroup analysis of patients with >12 months of growth remaining (n = 34) demonstrated no statistically significant changes in mean alignment or LLD. Before surgery, LLD was -1.39 mm and the injured limb was in significantly more valgus compared with the uninjured lower limb (mean difference: MAD, 4.79 mm [95% CI, 2.64 to 6.94 mm]; mLDFA, -0.93° [95% CI, -1.29° to -0.57°], and aLDFA, -0.91° [95% CI, -1.31° to -0.50°]). Conclusion: After ACLR, there were no statistically significant changes in mean alignment or longitudinal growth; however, 7 out of 104 patients (6.7%) demonstrated clinically significant changes in alignment or LLD. Preoperatively, the injured limb was statistically significantly in more valgus compared with the uninjured limb with lateralized MAD.

Ultrasonography or Radiography for Suspected Pediatric Distal Forearm Fractures.

BACKGROUND: Data on whether ultrasonography for the initial diagnostic imaging of forearm fractures in children and adolescents is noninferior to radiography for subsequent physical function of the arm are limited. METHODS: In this open-label, multicenter, noninferiority, randomized trial in Australia, we recruited participants 5 to 15 years of age who presented to the emergency department with an isolated distal forearm injury, without a clinically visible deformity, in whom further evaluation with imaging was indicated. Participants were randomly assigned to initially undergo point-of-care ultrasonography or radiography, and were then followed for 8 weeks. The primary outcome was physical function of the affected arm at 4 weeks as assessed with the use of the validated Pediatric Upper Extremity Short Patient-Reported Outcomes Measurement Information System (PROMIS) score (range, 8 to 40, with higher scores indicating better function); the noninferiority margin was 5 points. RESULTS: A total of 270 participants were enrolled, with outcomes for 262 participants (97%) available at 4 weeks (with a window of ±3 days) as prespecified. PROMIS scores at 4 weeks in the ultrasonography group were noninferior to those in the radiography group (mean, 36.4 and 36.3 points, respectively; mean difference, 0.1 point; 95% confidence interval [CI], -1.3 to 1.4). Intention-to-treat analyses (in 266 participants with primary outcome data recorded at any time) produced similar results (mean difference, 0.1 point; 95% CI, -1.3 to 1.4). No clinically important fractures were missed, and there were no between-group differences in the occurrence of adverse events. CONCLUSIONS: In children and adolescents with a distal forearm injury, the use of ultrasonography as the initial diagnostic imaging method was noninferior to radiography with regard to the outcome of physical function of the arm at 4 weeks. (Funded by the Emergency Medicine Foundation and others; BUCKLED Australian New Zealand Clinical Trials Registry number, ACTRN12620000637943).

Point-of-Care Ultrasound Fracture-Physis Distance Association with Salter-Harris II Fractures of the Distal Radius in Children: The "POCUS 1-cm Rule".

Salter-Harris II fractures of the distal radius can result in serious complications. The aim of this study was to measure the fracture-physis distance using point-of-care ultrasound (POCUS) to determine whether a certain distance is associated with Salter-Harris II fractures, compared with other fracture types, in a cohort of children with X-ray-identified distal radius fractures. Participants were from a parent diagnostic study conducted in an Australian tertiary pediatric emergency department, which prospectively evaluated the diagnosis of pediatric distal forearm fractures using POCUS compared against X-ray. Nurse practitioners, who underwent 2 h of training, administered a six-view POCUS protocol in clinically non-angulated pediatric forearm injuries prior to X-ray. This was a secondary analysis of data from the parent study. The 122 participants with X-ray-identified distal radius fractures from the parent study had their POCUS images interpreted by two emergency physician sonologists, who measured the fracture-physis distance. The median and maximum fracture-physis distances for Salter-Harris II fractures (n = 19) were 8.00 and 9.85 mm, whereas minimum and median distances for incomplete fractures (n = 22) were 10.20 and 15.98 mm, and those for complete fractures (n = 9) were 10.85 and 12.85 mm. Buckle fracture (n = 72) distances ranged from 4.35 to 26.55 mm, with a median of 13.65 mm. In children diagnosed with a distal radius fracture on X-ray, a fracture-physis distance cutoff of 1 cm differentiated Salter-Harris II fractures from other cortical breach fracture types, but not buckle fractures. Although this exploratory study suggests the "POCUS 1-cm rule" could be used as a secondary sign to augment the diagnosis of Salter-Harris II distal radius fractures using POCUS, further research is required to validate this measurement prospectively.

Single versus double hamstring tendon graft in anterior cruciate ligament reconstruction in the paediatric patient: a single-blind randomised controlled trial study protocol.

INTRODUCTION: There is currently no clear indication in the literature regarding a single or double hamstring tendon (single bundle) autograft for anterior cruciate ligament (ACL) reconstruction in the paediatric patient. The primary aim of this single blind randomised controlled trial is to determine whether a single or double hamstring tendon graft ACLR leads to superior clinical outcomes postsurgery in paediatric patients with ACL injury. METHODS AND ANALYSIS: Single site, prospective, single blind, randomised controlled trial with two parallel treatment arms. 100 patients aged 10-18 years who present with an isolated ACL tear±meniscal injury, verified on MRI, will be randomly allocated to one of the two surgical groups. The primary outcomes will be side-to-side difference in anterior tibial translation and graft failure incidence 12 months postsurgery. Primary and secondary outcomes will also be assessed at 2-year and 5-year postsurgery. ETHICS AND DISSEMINATION: Results will be presented in peer-reviewed journals and at international conferences and disseminated to participants and healthcare professionals via newsletters and hospital presentations. This study is approved by the Children's Health Queensland Hospital and Health Service Human Research Ethics committee. TRIAL REGISTRATION NUMBER: ACTRN12620001170910p; Australian New Zealand Clinical Trials Registry.

Kinematic differences in the presentation of recurrent congenital talipes equinovarus (clubfoot).

BACKGROUND: The tibialis anterior tendon transfer (TATT) is the suggested surgical intervention in the Ponseti method for treatment of dynamic recurrent congenital talipes equinovarus (clubfoot) presenting as hindfoot varus and forefoot supination during the swing phase of gait. The indication for surgery, however, is typically based on visual assessment, which does not sufficiently examine the variability of foot motion in this cohort. RESEARCH QUESTION: The aim of this research was to determine whether subgroups, based on foot model kinematics, existed within a clubfoot cohort being considered for TATT surgery. METHODS: Sixteen children with recurrent clubfoot that had been previously treated with the Ponseti method and were being considered for tendon transfer surgery were prospectively recruited for this study and were required to attend a pre-surgery data collection session at the Queensland Children's Motion Analysis Service (QCMAS). Data collected included standard Plug-in-Gait (PiG) kinematics and kinetics, Oxford Foot Model (OFM) foot kinematics, and regional plantar loads based on anatomical masking using the integrated kinematic-pressure method. RESULTS: Results of this study identified two clear subgroups within the cohort. One group presented with increased hindfoot inversion across 91 % of the gait cycle. The second group presented with increased hindfoot adduction across 100 % of the gait cycle. Hindfoot adduction was statistically significantly different between the two groups. SIGNIFICANCE: The identification of these two groups propose a need for further classification of deformity within this cohort and query the appropriateness of this surgical intervention for both presentations.

Establishing content validity of LIMB-Q Kids: a new patient-reported outcome measure for lower limb deformities.

PURPOSE: To establish the content validity of LIMB-Q Kids, a new patient-reported outcome measure (PROM) for children with lower limb deformities. This study focused on three key components of content validity, i.e., comprehension, comprehensiveness, and relevance. METHODS: Cognitive debriefing interviews (CDIs) with children with lower limb deformities were performed, and expert input from parents and clinicians directly involved in the care of children with lower limb deformities was obtained. CDIs were conducted with children from sites in Australia, Canada, and the USA. All interviews were recorded and transcribed verbatim. Analyses were conducted using the reparative approach, which involved close examination of the transcribed interviews and summarising edits after each interview. RESULTS: Forty patients, experts, and parents reviewed LIMB-Q Kids and provided feedback. At the start, LIMB-Q Kids had 10 scales and 124 total items. Five rounds of input was obtained from children, parents, and experts. Overall, 37 new items were added. Thirty-three of the new items were included to measure symptoms experienced in different parts of the legs. Final version of LIMB-Q Kids had 11 scales and 159 items. CONCLUSION: This study established content validity of the LIMB-Q Kids, a new PROM for children with lower limb deformities. An international field-test study is underway. Translation and cultural adaptation are underway for sites where English is not the first language. Scoring algorithms will be developed, following which the scale could be used to inform clinical practice and research.

Targeted Quantitative Profiling of GTP-Binding Proteins Associated with Metastasis of Melanoma Cells.

Metastasis is a major obstacle in the therapeutic intervention of melanoma, and several GTP-binding proteins were found to play important roles in regulating cancer metastasis. To assess systematically the regulatory roles of these proteins in melanoma metastasis, we employed a targeted chemoproteomic method, which relies on the application of stable isotope-labeled desthiobiotin-GTP acyl phosphate probes in conjunction with scheduled multiple-reaction monitoring (MRM), for profiling quantitatively the GTP-binding proteins. Following probe labeling, tryptic digestion, and affinity pull-down of desthiobiotin-conjugated peptides, differences in expression levels of GTP-binding proteins in two matched pairs of primary/metastatic melanoma cell lines were measured using liquid chromatography-MRM analysis. We also showed that among the top upregulated proteins in metastatic melanoma cells, AK4 promotes the migration and invasion of melanoma cells; overexpression of AK4 in primary melanoma cells leads to augmented migration and invasion, and reciprocally, knockdown of AK4 in metastatic melanoma cells results in repressed invasiveness. In summary, we examined the relative expression levels of GTP-binding proteins in two pairs of primary/metastatic melanoma cell lines. Our results confirmed some previously reported regulators of melanoma metastasis and revealed a potential role of AK4 in promoting melanoma metastasis.

Plantar load transfer in children: a descriptive study with two pathological case studies.

BACKGROUND: Typical gait is often considered to be highly symmetrical, with gait asymmetries typically associated with pathological gait. Whilst gait symmetry is often expressed in symmetry ratios, measures of symmetry do not provide insight into how these asymmetries affect gait variables. To fully understand changes caused by gait asymmetry, we must first develop a normative database for comparison. Therefore, the aim of this study was to describe normative reference values of regional plantar load and present comparisons with two pathological case studies. METHODS: A descriptive study of the load transfer of plantar pressures in typically developed children was conducted to develop a baseline for comparison of the effects of gait asymmetry in paediatric clinical populations. Plantar load and 3D kinematic data was collected for 17 typically developed participants with a mean age of 9.4 ± 4.0 years. Two case studies were also included; a 10-year-old male with clubfoot and an 8-year-old female with a flatfoot deformity. Data was analysed using a kinematics-pressure integration technique for anatomical masking into 5 regions of interest; medial and lateral forefoot, midfoot, and medial and lateral hindfoot. RESULTS: Clear differences between the two case studies and the typical dataset were seen for the load transfer phase of gait. For case study one, lateral bias was seen in the forefoot of the trailing foot across all variables, as well as increases in contact area, force and mean pressure in the lateral hindfoot of the leading foot. For case study two, the forefoot of the trailing foot produced results very similar to the typical dataset across all variables. In the hindfoot of the leading foot, medial bias presents most notably in the force and mean pressure graphs. CONCLUSIONS: This study highlights the clinical significance of the load transfer phase of gait, providing meaningful information for intervention planning.

Bedside Ultrasound Conducted in Kids with distal upper Limb fractures in the Emergency Department (BUCKLED): a protocol for an open-label non-inferiority diagnostic randomised controlled trial.

BACKGROUND: Children frequently present to the emergency department (ED) with forearm injuries and often have x-rays to determine if there is a fracture. Bedside ultrasound, also known as point-of-care ultrasound (POCUS), is an alternative diagnostic test used to rapidly diagnose a fracture at the time of examination, without exposing children to ionising radiation. Prospective studies have demonstrated high agreement between POCUS and x-ray findings. However, whether the initial imaging modality affects the patient's medium-term physical function is unknown. METHODS: This is a multicentre, open-label, non-inferiority randomised controlled trial conducted in Australian EDs. Recruitment will continue until 112 children with distal forearm injuries (including 48 buckle fractures) per trial arm have achieved the primary outcome measure. Patients aged 5-15 years presenting with an isolated, acute, clinically non-angulated, distal forearm injury with suspected fracture will have their initial diagnostic approach randomised to either POCUS, performed by a credentialled practitioner, or x-ray imaging. If a cortical breach fracture is identified on POCUS, the patient will receive x-rays and have usual care. If a buckle fracture is identified, the patient will have their forearm placed in a splint and be discharged home. Patients will be followed up at 1, 4 and 8 weeks. The primary outcome is upper limb physical function at 4 weeks, as determined by the Pediatric Upper Extremity Short Patient-Reported Outcomes Measurement Information System (PROMIS) tool. Secondary outcomes include healthcare costs, satisfaction, pain, complications, rates of imaging, ED length of stay and diagnostic accuracy. DISCUSSION: If POCUS is non-inferior to x-ray in terms of patient's medium-term physical function, it may have an effect on overall health care resource use, including the number of x-ray performed and earlier ED discharge. Although prospective studies have confirmed the accuracy of POCUS, this will be the first RCT to assess non-inferiority of functional outcomes of POCUS to diagnose non-angulated paediatric distal forearm injuries, compared to x-ray. POCUS may be of particular importance in settings where access to x-ray imaging can be limited either during or after-hours, as it can aid the triaging and management of patients. TRIAL REGISTRATION: Prospectively registered with the ANZCTR on 29 May 2020 ( ACTRN12620000637943 ).

Targeted Proteomic Analysis Revealed Kinome Reprogramming during Acquisition of Radioresistance in Breast Cancer Cells.

Radiotherapy constitutes a major therapeutic modality for early management of breast cancer. Despite the high efficacy in treating breast cancer (BC), radiation resistance and tumor recurrence are major hurdles in breast cancer radiotherapy. Herein, stable isotope labeling by amino acids in cell culture (SILAC) was employed, along with the parallel-reaction monitoring (PRM)-based targeted quantitative proteomic method, to examine the differences in kinase protein expression in MCF-7 and MDA-MB-231 breast cancer cells and their corresponding radioresistant C6 and C5 clones. We quantified the relative protein expression levels of 300 and 281 kinases in C5/MDA-MB-231 and C6/MCF-7 pairs of breast cancer cells, respectively. We also showed that TAF9, which was one of the differentially expressed kinases, enhances radiation resistance in breast cancer cells. Moreover, a correlation analysis of gene expression suggested TAF9's role in upregulating the expression of genes involved with radioresistance. Overall, our study uncovered a large number of differentially expressed kinases accompanied with the acquisition of radioresistance and revealed a role of TAF9 in promoting radioresistance in breast cancer.

Modulation of N-terminal methyltransferase 1 by an N6-methyladenosine-based epitranscriptomic mechanism.

Protein α-N-methylation is an evolutionarily conserved type of post-translational modification; however, little is known about the regulatory mechanisms for this modification. Methylation at the N6 position of adenosine in mRNAs is dynamic and modulates their stability, splicing, and translational efficiency. Here, we found that the expression of N-terminal methyltransferase 1 (NTMT1) protein is altered by depletion of those genes encoding the reader/writer/eraser proteins of N6-methyladenosine (m6A). We also observed that MRG15 is N-terminally methylated by NTMT1, and this methylation could also be modulated by reader/writer/eraser proteins of m6A. Together, these results revealed a novel m6A-based epitranscriptomic mechanism in regulating protein N-terminal methylation.

Nurse practitioner administered point-of-care ultrasound compared with X-ray for children with clinically non-angulated distal forearm fractures in the ED: a diagnostic study.

BACKGROUND: Paediatric distal forearm fractures are a common ED presentation. They can be diagnosed with point-of-care ultrasound (POCUS) as an alternative to X-rays. Given that ED nurse practitioners (NPs) are relied on for the diagnosis of paediatric fractures, it is important to describe the diagnostic accuracy of NP-conducted POCUS versus X-ray. METHODS: This prospective diagnostic study was conducted in a tertiary paediatric hospital in Queensland, Australia, between February 2018 and April 2019. Participants were children aged 4-16 years with a clinically non-angulated, suspected distal forearm fracture. Diagnosis from 6-view NP-administered POCUS of the distal radius and ulna was compared against the reference standard of 2-view X-ray. Each patient received both imaging modalities. Overall forearm diagnosis was classified as 'no', 'buckle' or 'other' fracture for both modalities. The primary outcome was diagnostic accuracy for 'any' fracture ('buckle' and 'other' fractures combined). Secondary outcomes included diagnostic accuracy for 'other' fractures versus 'buckle' and 'no' fractures combined, and pain, imaging duration and preference for modality. RESULTS: Of 204 recruited patients, 129 had X-ray-diagnosed forearm fractures. The sensitivity and specificity for NP-administered POCUS were 94.6% (95% CI 89.2% to 97.3%) and 85.3% (95% CI 75.6% to 91.6%), respectively. 'Other' fractures (mostly cortical breach fractures), when compared with 'buckle'/ 'no' fractures, had sensitivity 81.0% (95% CI 69.1% to 89.1%) and specificity 95.9% (95% CI 91.3% to 98.1%). Pain and imaging duration were clinically similar between modalities. There was a preference for POCUS by patients, parents and NPs. CONCLUSIONS: NP-administered POCUS had clinically acceptable diagnostic accuracy for paediatric patients presenting with non-angulated distal forearm injuries. This included good sensitivity for diagnosis of 'any' fracture and good specificity for diagnosis of cortical breach fractures alone. Given the preference for POCUS, and the lack of difference in pain and duration between modalities, future research should consider functional outcomes comparing POCUS with X-ray in this population in a randomised controlled trial.

Adenylate Kinase 4 Modulates the Resistance of Breast Cancer Cells to Tamoxifen through an m6A-Based Epitranscriptomic Mechanism.

N6-methyladenosine (m6A) is the most abundant internal modification in mRNA and this methylation constitutes an important regulatory mechanism for the stability and translational efficiency of mRNA. In this study, we found that the protein levels of adenylate kinase 4 (AK4) and m6A writer METTL3 are significantly higher in tamoxifen-resistant (TamR) MCF-7 cells than in parental cells. The TamR MCF-7 cells also exhibit increased methylation at multiple m6A consensus motif sites in the 5' untranslated region (5' UTR) of AK4 mRNA, and genetic depletion of METTL3 in TamR MCF-7 cells led to a diminished AK4 protein level and attenuated resistance to tamoxifen. In addition, we observed augmented levels of reactive oxygen species (ROS) and p38 activity in TamR MCF-7 cells, and both are diminished upon genetic depletion of AK4. Reciprocally, overexpression of AK4 in MCF-7 cells stimulates ROS and p38 phosphorylation levels, and it suppresses mitochondrial apoptosis. Moreover, scavenging of intracellular ROS leads to reduced p38 activity and re-sensitizes TamR MCF-7 cells to tamoxifen. Thus, our results uncover a novel m6A-mediated epitranscriptomic mechanism for the regulation of AK4, illustrate the cellular pathways through which increased AK4 expression contributes to tamoxifen resistance, and reveal AK4 as a potential therapeutic target for overcoming tamoxifen resistance.