Rapid screening for the posterior fat pad sign in suspected pediatric elbow fractures using point-of-care ultrasound: a “FAST exam” for the traumatized elbow

The diagnostic value of sonographic findings in pediatric elbow fractures: A systematic review and meta-analysis

BACKGROUND

Sonography is a beneficial imaging modality for detecting elbow fractures in children, considering the lack of radiation exposure and time efficiency. This systematic review aims to determine the diagnostic value and clinical applicability of sonography and each sonographic finding in detecting pediatric elbow fractures.

METHODS

Pubmed, Scopus, and WOS databases were searched for related original articles until February 25, 2023, and data related to diagnostic performance were extracted. We used the Bivariate model and hierarchic summary receiver operating characteristic (HSROC) approach to calculate pooled diagnostic values. Cochrane Q test and I-squared were performed to evaluate heterogeneity. We assessed heterogeneity with meta-regression.

RESULTS

Eight studies were included, which involved a total number of 880 patients. According to meta-analysis, sonography demonstrated a pooled sensitivity of 97% (91-99%) and specificity of 90% (80-95%), positive likelihood ratio(LR+) of 9.82 (4.59-20.97), and negative likelihood ratio (LR-) of 0.03 (0.01-0.10). For the sonographic posterior fat pad sign as a sole diagnostic sign, we calculated a Pooled Sensitivity of 80% (70-88%), Specificity of 97% (87-99%), LR+ of 28.8 (6-139.3), and LR- of 0.2 (0.13-0.31). Also, lipohemarthrosis demonstrated a pooled sensitivity of 80% (70-88%), specificity of 97% (87-99%), LR+ of 28.8 (6-139.3), and LR- of 0.2 (0.13-0.31). The sensitivity of detecting fractures with cortical line disruption was significantly higher in studies that utilized a comprehensive technique compared to a conventional technique.

CONCLUSIONS

Sonography is a valuable diagnostic tool for the assessment of pediatric elbow injuries, and it can be capable of confirmation or exclusion of the diagnosis.

Effectiveness of ultrasonography performed at the emergency department for pediatric elbow trauma cases

BACKGROUND

Two-way direct radiography is the first-choice imaging method for pediatric patients presenting to the emergency department with elbow trauma. Although, unlike radiography, ultrasonography (US) is not used routinely, studies show that US can be used in the diagnosis of fractures in pediatric patients.

METHODS

In this single-center prospective observational study, patients under the age of 18 who presented to the emergency department after sustaining elbow trauma constituted the population of the study. Findings of the posterior fat pad sign using bedside US and the result obtained by seven-point assessment of the bone cortex were compared with the final diagnosis.

RESULTS

Of the 128 patients enrolled in the study, 6 patients were excluded due to various reasons. Seventy (57.4%) patients were male, and median age was 7.7 years. On examining the final diagnosis of the patients at the emergency department, fracture diagnosis was observed in 39 patients (32%). It was determined that fracture diagnosis for 94.9% of the patients included in the study could be achieved using US (in the presence of at least the fat pad sign and/or direct findings of fracture based on the seven-point assessment).

CONCLUSION

US should be considered as a diagnostic tool in cases of pediatric elbow traumas owing to its high sensitivity and negative predictive value. US, which is reproducible, ionizing radiation-free, and can be performed at the bedside, can considerably reduce unnecessary radiography in low-risk patients when evaluated along with physical examination findings among patients in the pediatric age group presenting with elbow trauma. We believe that the result of our study will contribute to patient care practices.

Comparison of ultrasonography and conventional radiography in the diagnosis of extremity fractures in the emergency department

Objective: The purpose of the study is to compare the diagnostic accuracy (sensitivity and specificity) of ultrasonography (USG) with that of conventional radiography (CR), the standard imaging modality used to diagnose acute extremities fractures. Materials and Methods: The prospective investigation examined 245 patients with clinical symptoms of an extremity fracture. Radiography (anteroposterior and lateral radiographs for each patient, oblique if necessary) and USG were performed on all participants and compared with all the results. Results: CR verified 98.5% of 132 patients who were determined to have extremities fractures with USG. CR, on the other hand, confirmed 99.1% of 112 patients who were reported to have no extremities fractures by USG. The sensitivity (detection of fractures based on USG of patients with fractures detected based on the CR imaging) was 99.2% (95%CI=95.8-99.9); selectivity (no fracture was detected based on USG of patients with no fracture detected based on the CR imaging) was 98.2% (95%CI=93.8-99.7); the positive predictability was 98.48% (95%CI=94.2-99.6), whereas the negative predictability value was 99.1%(95%CI=94-99.8). Conclusion: USG and CR showed similar diagnostic performances in the diagnosis of extremity fractures. USG can be considered an alternative to CR in the examination of extremity fractures with comparable diagnostic performance.

Diagnostic accuracy of ultrasonography for diagnosis of elbow fractures in children

BACKGROUND

Elbow injuries and fractures are a common pathology in the pediatric emergency unit. X-ray and CT scan of the elbow are the standard diagnostic procedures, which increase exposure to radiation in children. Previous studies have shown that fractures can also be visualized by ultrasound (US); thus, this study aimed to evaluate the diagnostic accuracy of elbow US compared with radiography for the diagnosis of elbow fracture in children.

MATERIALS AND METHODS

This was a prospective observational study of patients aged 2-14 years that presented to emergency departments with a suspected elbow fracture requiring radiographic evaluation. Elbow US for diagnosing elevated posterior fat pad or lipohemarthrosis was performed. All patients underwent elbow radiography and received clinical follow-up. Initial or follow-up X-ray or CT scan was used as the reference standard for fracture diagnosis.

RESULTS

Seventy-five patients with a mean age of 6.51 ± 3.68 years were enrolled in the study. Twenty-eight (37.3%) patients had positive results for fracture. The sensitivity, specificity, and accuracy of US in the diagnosis of elbow fractures were 92.9% (95% CI 76.5-99.1%), 89.4% (95% CI 76.9-96.5%) and 90.7% (95% CI 81.7-96.2%). In patients with fracture, US demonstrated a lipohaemarthrosis in 20 patients (71.4%), elevated posterior fat pad in 19 patients (67.9%), cortical disruption in 10 patients (35.7%), and effusion in three patients (10.7%).

CONCLUSION

Our results showed high diagnostic accuracy for the ultrasonography diagnosis of an elbow fracture, which allows us to confirm ultrasonography imaging of the elbow as a safe alternative in the primary evaluation of pediatric elbow injuries.

Diagnostic Performance of Ultrasonography for Detection of Pediatric Elbow Fracture: A Meta-analysis

STUDY OBJECTIVE

We evaluate the diagnostic performance of ultrasonography for detection of elbow fracture in pediatric patients with trauma.

METHODS

PubMed and EMBASE databases were searched for diagnostic accuracy studies that used ultrasonography for detection of elbow fracture in pediatric patients. Bivariate modeling and hierarchic summary receiver operating characteristic (ROC) modeling were conducted to evaluate diagnostic performance. The pooled proportions of the false-negative rate were assessed with a DerSimonian-Laird random-effects model. We performed meta-regression analyses for heterogeneity exploration.

RESULTS

Ten articles involving a total of 519 patients were included. The summary sensitivity, summary specificity, and area under the hierarchic summary ROC curve were 96% (95% confidence interval 88% to 99%), 89% (95% confidence interval 82% to 94%), and 0.97 (95% confidence interval 0.95 to 0.98), respectively. The pooled proportion of the false-negative rate of ultrasonography was 3.7%. Among the various potential covariates, ultrasonographic performer (pediatric emergency physician versus others) and presence of extra musculoskeletal ultrasonographic training (trained versus not reported) were associated with heterogeneity of the specificity.

CONCLUSION

Elbow ultrasonography demonstrated high performance in the diagnosis of pediatric elbow fracture, particularly in studies of physicians with extra training in musculoskeletal ultrasonography. Ultrasonography may be performed by trained physicians as a first-line diagnostic tool to diagnose pediatric elbow fracture.

The role of ultrasound as a problem-solving tool in the assessment of paediatric musculoskeletal injuries

Musculoskeletal trauma in the paediatric population covers a wide range of injuries; although many overlap with their adult counterparts, others are exclusive to the immature skeletal system. Ultrasound is a versatile tool particularly suited to both the imaging of children and the dynamic assessment of musculoskeletal injuries. This pictorial review aims to discuss a range of injuries, focusing on those commonly encountered in children. We shall describe the muscle-tendon-bone complex and changes that occur with increasing skeletal maturity and how this affects the type of injury encountered.

Ultrasound findings of the elbow posterior fat pad in children with radial head subluxation

OBJECTIVE

The aim of this study was to determine whether elbow ultrasound findings of the posterior fat pad (PFP) are present in patients with diagnosis of radial head subluxation (RHS).

METHODS

This was a prospective study of children presenting to an urban pediatric emergency department diagnosed clinically with RHS. Physicians received a 1-hour training session on musculoskeletal ultrasound including the elbow. Before performing reduction for RHS, the physicians performed a brief, point-of-care elbow ultrasound using a high-frequency linear transducer probe in both longitudinal and transverse views to evaluate for PFP elevation and lipohemarthrosis (LH). Successful clinical reduction with spontaneous movement of injured extremity served as the criterion standard for RHS. Clinical telephone follow-up was performed to ascertain outcomes.

RESULTS

Forty-two patients were enrolled with a mean age of 22.3 (11.8) months. The mean time to presentation was 7 (9.2) hours, and 9/42 (21%) children had previous history of RHS. The majority of patients (35/42, 83%; 95% confidence interval (CI), 69%-92%) had a normal elbow ultrasound. Of 42 patients, 6 (14%; 95% CI 6%-28%) had an elevated PFP and 2 (5%; 95% CI, 0.5%-17%) had LH. Clinical reduction was successful in 100% of patients, and there were no complications reported on follow-up.

CONCLUSIONS

The majority of children with RHS have a normal PFP on elbow ultrasound, but elevated PFP and LH are possible findings. Reduction maneuvers for RHS may be attempted in patients with a normal elbow ultrasound when the diagnosis of RHS or elbow fracture is uncertain.

Accuracy of clinician-performed point-of-care ultrasound for the diagnosis of fractures in children and young adults

INTRODUCTION

Injury is a major cause of death and disability in children and young adults worldwide. X-rays are routinely performed to evaluate injuries with suspected fractures. However, the World Health Organisation estimates that up to 75% of the world population has no access to any diagnostic imaging services. Use of clinician-performed point-of-care ultrasound to diagnose fractures is not only feasible in traditional healthcare settings, but also in underserved or remote settings. Our objective was to determine the accuracy of clinician-performed point-of-care ultrasound for the diagnosis of fractures in children and young adults presenting to an acute care setting.

METHODS

We conducted a prospective cohort study of patients aged <25 years that presented to emergency departments with injuries requiring X-rays or CT for suspected fracture. Paediatric emergency physicians with a 1h training session diagnosed fractures by point-of-care ultrasound. X-rays or CT were used as the reference standard to determine test performance characteristics.

RESULTS

Point-of-care ultrasound was performed on 212 children and young adults with 348 suspected fractures. Forty-two percent of all bones imaged were non-long bones. The prevalence rate of fracture was 24%. Overall: sensitivity-73% (95% CI: 62-82%), specificity-92% (95% CI: 88-95%); long bones: sensitivity-73% (58-84%), specificity-92% (86-95%); non-long bones: sensitivity-77% (58-90%); specificity-93% (87-97%); age> or =18 years: sensitivity-60% (39-78%), specificity-92% (87-96%); age<18: sensitivity-78 (65-87%), specificity-93% (87-95)%. Majority of errors in diagnosis (>85%) occurred at the ends-of-bones.

CONCLUSIONS

Clinicians with focused ultrasound training were able to diagnose fractures using point-of-care ultrasound with a high specificity rate. Specificity rates to rule-in fracture were similar for non-long bone and long bone fractures, as well as in skeletally mature young adults and children with open growth plates. Clinician-performed point-of-care ultrasound accuracy was highest at the diaphyses of long bones, while most diagnostic errors were committed at the ends-of-bones or near joints. Point-of-care ultrasound may serve as a rapid alternative means to diagnose midshaft fractures in settings with limited or no access to X-ray.