Accuracy of the sonographic fat pad sign for primary screening of pediatric elbow fractures: a preliminary study.
OBJECTIVE
The purpose of this study was to evaluate the diagnostic accuracy of the sonographic fat pad sign (FPS) as a predictor for pediatric elbow fractures.


METHODS
This is a prospective study of children under 14 years with suspected elbow fractures. All participants underwent at first ultrasonography focused on a FPS followed by standard elbow radiographs. US findings were compared to final fracture diagnosis.


RESULTS
38 out of 79 children had an elbow fracture. A sonographic FPS predicted an elbow fracture with a sensitivity/specificity of 97.3/90.5 %, positive/negative likelihood ratios (LR) were 10.2/0.03 and correct/false classification rates were 93.7/6.3 %. Primary US findings were later reviewed by a blinded physician giving a congruity of 96.2 %. These secondary US findings predicted an elbow fracture with a sensitivity/specificity of 92.1/92.7 %, positive/negative LRs were 12.6/0.09 and correct/false classification rates were 92.4/7.5 %.


CONCLUSIONS
The sonographic FPS could serve as a useful screening tool in primary evaluation of pediatric elbow injuries. If a fracture is unlikely after clinical and US evaluation, additional radiographs are dispensable, thereby potentially minimizing the radiation burden in childhood and reducing the length of stay in the Emergency Department.
Department for Pediatric Surgery, Elisabeth Hospital Essen, Klara-Kopp-Weg 1, 45138, Essen, Germany. eckert.kolja@me.com.
Kolja
K
Eckert
Department for Orthopaedics, Trauma- and Reconstructive Surgery, Evangelic Hospital Oberhausen, Virchowstrasse 20, 46047, Oberhausen, Germany.
Ole
O
Ackermann
Department for Pediatric Surgery, Elisabeth Hospital Essen, Klara-Kopp-Weg 1, 45138, Essen, Germany.
Niklas
N
Janssen
Department for Diagnostical und Interventional Radiology and Neuroradiology, Universitary Hospital Essen, Hufelandstraße 55, 45147, Essen, Germany.
Bernd
B
Schweiger
Department for Pediatric Surgery, Elisabeth Hospital Essen, Klara-Kopp-Weg 1, 45138, Essen, Germany.
Elke
E
Radeloff
Department for Pediatric Surgery, Elisabeth Hospital Essen, Klara-Kopp-Weg 1, 45138, Essen, Germany.
Peter
P
Liedgens
D000273:Adipose Tissue / Q000000981:diagnostic imaging*; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004550:Elbow / Q000000981:diagnostic imaging*; D050723:Fractures, Bone / Q000000981:diagnostic imaging*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007223:Infant; D011446:Prospective Studies; D011859:Radiography; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000379:methods*; D000092464:Elbow Injuries
Children; Elbow; Fat pad sign; Fracture; Ultrasound