What is your diagnosis?

This is a normal radiograph for the patient’s age. The bone that appears separate  near his olecranon are part of his regular ossification center.

• Pearl: The pediatric elbow has multiple ossification centers that can make reading radiographs challenging. The pattern of ossification generally follows the mnemonic CRITOE, although ages can vary greatly by patient. The chart below gives approximated years of appearance for reference.

Image 2: Fully ossified elbow with centers labeled. Case courtesy of Dr Andrew Dixon, Radiopaedia.org, rID: 20908

Image 3: Ossification in 2 year old for comparison. Case courtesy of Dr Andrew Dixon, Radiopaedia.org, rID: 20908

• Pearl: Comparisons to normal pediatric imaging of similar age can be helpful when determining if there is pathology. Check out The Bone Pit - a free online favorite of the author. 

What common pediatric elbow findings are you looking for? How do you evaluate?

Fat pads: 

Posterior Fat Pad: Always pathologic, even if no fracture is seen. In pediatrics it commonly signifies a supracondylar fracture, whereas in adults it is generally a radial head fracture [1].

Anterior Fat Pad: Routinely a normal finding, though larger sizes can also be pathologic (such as in the image below).

• More than 15 degrees of angulation indicates likely effusion [2].

Image 4: Type I supracondylar fracture with anterior (blue) and posterior (orange) fat pads labeled. Case with annotations courtesy of Richard Hopkins, MD

Lines:

Anterior Humeral Line: Drawn down the anterior humeral shaft, it should intersect the middle ⅓ of the capitellum. If it doesn’t, consider a supracondylar fracture. See Image 5.

Radiocapitellar Line: Drawn along the radial neck, it should intersect the capitellum. If it doesn’t, consider a radial head dislocation or fracture. See Image 6.

Image 5: Anterior humeral line. Case courtesy of Dr Benoudina Samir, Radiopaedia.org,  rID: 41196

Image 6: Radiocapitellar line. Case courtesy of Dr Benoudina Samir, Radiopaedia.org,  rID: 41196

Cortices:

Observe each edge for cracks, widening, or abnormal lucencies, especially the radial head and olecranon.

• Pearl: Consider ultrasound as an adjunctive imaging modality for evaluation of an intra-articular effusion [3].

What is your management and disposition in the ED?

This patient’s family can be reassured and given instructions for symptomatic treatment. Follow-up can occur with a pediatrician as needed. 

If there is no radiographic evidence, but there is clinical concern for a fracture, consider temporary immobilization with a sling or posterior long arm splint. Ensure close follow up in 1 week for re-evaluation and repeat x-rays. Long periods of immobilization may result in complications such as contractures, muscle atrophy, neuropraxia, infections, and ulcers.

Do you consult orthopedics?

With a normal x-ray for age, no consult is needed. As per above, the patient can follow up outpatient as needed.