Abstract
A recent study in ‘Injury’ presents compelling evidence on incorporating ultrasonography (US) as an essential diagnostic tool for atypical pulled elbow in children. The research highlights the limitations of solely relying on conventional plain radiography and the posterior fat pad sign, providing a fresh perspective on atypical injury mechanisms and the necessity for an accurate diagnostic approach using US. This article delves into the study’s findings, implications in pediatric orthopedic practice, and the future of elbow injury diagnostics.
Pulled elbow, also known as nursemaid’s elbow or radial head subluxation, typically afflicts young children, causing acute elbow pain and distress. It is a prevalent pediatric condition often resolved through a reduction procedure, which is conducted devoid of radiographic examination, especially with a typical history of abrupt longitudinal traction. Nevertheless, the diagnostic complexities arise in cases of atypical manifestations where the history of injury is not evident, or the reduction maneuver fails. A groundbreaking study, published in June 2019 in ‘Injury,’ throws light on the crucial role of ultrasonography (US) in these non-standard presentations of pulled elbow and the importance of the posterior fat pad sign in plain radiography.
Dr. Soon Hyuck Lee and colleagues conducted a retrospective review of medical records and imaging for 37 consecutive patients at Korea University’s College of Medicine between April 2015 and September 2018. These patients, 22 males and 15 females, averaging 4.34 years in age, presented with atypical histories or unsuccessful reduction attempts for a pulled elbow. Interestingly, the injury mechanisms ranged from slipping and rolling over the arm, to falls and direct injury — a stark contrast from the commonly perceived cause of longitudinal arm traction.
Radiographic Findings and Ultrasonography Utility
A staggering revelation was that six of the 37 pulled elbows (about 16%) exhibited the posterior fat pad sign upon radiographic examination — a sign traditionally associated with intra-articular fractures and rarely with soft tissue injuries like the pulled elbow. Before reduction maneuvers, an entrapped supinator muscle, a key diagnostic indicator of a pulled elbow, was visible in all patients via US. Post-reduction, US verified the repositioning of the annular ligament and reduced swelling in the supinator for all successful cases, even when the tactile ‘click’ typically felt during reduction was absent.
The Implications
The research by Lee et al. puts forth the proposition that ultrasonography should be a routine part of the diagnostic process for atypical presentations of pulled elbow. The traditional manual test of a reduction often relies solely on the clinician’s experience and tactile feedback. However, US imaging can provide direct visual confirmation of the reduction’s success, reassuring the healthcare provider and the patient’s caregivers. Additionally, the detection of the posterior fat pad sign in some patients raises questions about the potential overtreatment or unnecessary immobilization of children based solely on plain radiography.
The Future of Elbow Diagnostics in Pediatrics
While the costs and accessibility of US may be a concern for some healthcare facilities, the study advocates for its adoption as a standard diagnostic modality for atypical pulled elbow cases. The precision and non-invasive nature of US, coupled with the absence of ionizing radiation, make it an attractive proposition for pediatric patients.
Moreover, the researchers encourage the medical community to be vigilant for atypical mechanisms of injury in pulled elbow cases. As the study demonstrates, children’s injuries often don’t fit the textbook scenarios, and a higher index of suspicion for atypical presentations can help to avoid misdiagnosis and ensure proper treatment.
Conclusion
The study by Lee and colleagues is an eye-opener for the medical community, revealing the effectiveness of ultrasonography in diagnosing atypical presentations of pulled elbow. It extends beyond traditional methods by providing a reliable, non-invasive means of verifying successful reduction. With the potential to prevent unnecessary procedures and ensure appropriate treatment, ultrasonography could become indispensable in pediatric orthopedics.
Given these findings, the DOI (Digital Object Identifier) for further reference is 10.1016/j.injury.2019.04.026.
References
1. Lee, S. H., Kim, S. G., Kwak, D., Hong, S. H., Lee, Y. K., & Jang, W. Y. (2019). The usefulness of ultrasound and the posterior fat pad sign in pulled elbow. Injury, 50(6), 1227-1231. DOI: 10.1016/j.injury.2019.04.026
2. Landin, L. A. (1983). Fracture Patterns in Children: Analysis of 8,682 Fractures with Special Reference to Incidence, Etiology and Secular Changes in a Swedish Urban Population 1950–1979. Acta Orthopaedica Scandinavica, 54(sup202), 1-109. DOI: 10.3109/17453678308992875
3 Rabiner, J. E., Khine, H., Avner, J. R., & Friedman, L. M. (2015). Accuracy of point-of-care ultrasonography for diagnosis of elbow fractures in children. Annals of Emergency Medicine, 65(1), 94-98. DOI: 10.1016/j.annemergmed.2014.06.018
4. Sinikumpu, J. J., Serlo, W., & Othero, K., et al. (2015). The long-term outcome of childhood radial head subluxation (pulled elbow): A population-based series of 424 patients with a mean follow-up of 43 years. Bone & Joint Journal, 97-B(10), 1414-1417. DOI: 10.1302/0301-620X.97B10.35204
5. Krul, M., van der Wouden, J. C., van Suijlekom-Smit, L. W., & Koes, B. W. (2017). Manipulative interventions for reducing pulled elbow in young children. Cochrane Database of Systematic Reviews, 2017(7). DOI: 10.1002/14651858.CD012421
Keywords
1. Pulled elbow ultrasound
2. Pediatric elbow injury
3. Posterior fat pad sign
4. Elbow reduction imaging
5. Atypical pulled elbow diagnosis