Presentation
Fall onto the flexed elbow. Tender to the touch.
Patient Data
Elbow radiographs revealed a fragment near the trochlea.
The fragment should not be confused with an ossification center (see annotated image and case discussion below).
Annotated images point to the capitellum and radial head ossification centers, which are normal for the patient's age.
What is not normal, however, is the highlighted olecranon fragment. That location is not typical of any ossification center. Also, unlike a proper ossification center, its borders are rough.
Case Discussion
This case illustrates the importance of being familiar with the elbow ossification centers when assessing a pediatric elbow.
In a pediatric elbow radiograph evaluation, it is important to be familiar with the expected ossification centers' appearance by age. They can be remembered using the CRITOE mnemonic:
- C: capitellum
- R: radial head:
- I: Internal (medial) epicondyle
- T: trochlea
- O: olecranon
- E: external (lateral) epicondyle
In this case, the patient is 5-years old. At this age, the expected visible ossification centers should be the capitellum and radial head ones, the medial epicondyle one could also be present, but should not be so developed. That means the finding is a bone fragment.
The cortical interruption at the proximal posterolateral cortical of the ulna allows for the fragment to be identified as an olecranon fracture.