Comment

The radial head fracture is most convincingly demonstrated on the 45 degree radial head view. This is often the case with radial head fractures.

This 38 year old male presented to the Emergency Department following a fall onto an outstretched hand . He had pain in his right elbow and a limited range of movement. He was referred for elbow radiography.

	The AP elbow view demonstrates the patient has achieved a full extended elbow position. There is no displaced fracture demonstrated
	This is a good lateral elbow position There is an anterior fatpad sign ( white arrow) There is a posterior fatpad sign (black arrow) The supinator fat pad is not well seen There is no displaced fracture demonstrated
	The mechanism of injury and the fatpad signs demonstrated on the routine views warranted further imaging The 45 degree radial head view image demonstrates no radial head fracture conclusively.

Comment

It is possible that this patient has not sustained any bony injury. It is equally possible that the patient has an undisplaced radial head fracture that has not been demonstrated on this examination.

This 15 year old male presented to the Emergency Department following a fall onto an outstretched hand after falling off his pushbike. He had pain in his right elbow and a decreased range of movement. He was referred for elbow radiography.

	The AP elbow position appears to be over-rolled into an oblique position. This demonstrates the radial head well but was not the intended position. The bony anatomy is unremarkable
	This is a slightly malpositioned lateral elbow view. There is an anterior fatpad sign ( longer white arrow) There is a posterior fatpad sign (short white arrow) The supinator fat pad is not well seen There is discontinuity of the contour of the radial head suggesting a radial head fracture
	The mechanism of injury and the fatpad signs demonstrated on the routine views warranted further imaging The 45 degree radial head view image demonstrated a similar discontinuity of the radial head It is likely that the patient had a type I radial head fracture

This 56 year old lady presented to the Emergency Department following a fall from steps onto an outstretched hand . She had pain in her right elbow and a decreased range of movement. She was referred for elbow radiography.

	The AP elbow position appears to be slightly under-rolled into a partly reverse oblique position. This tends to superimpose the medial aspect of the radius over the olecranon. There is evidence of a radial head fracture (arrowed)
	This is an attempted oblique elbow position that appears to be closer to an AP elbow position. The radial head fracture is clearly demonstrated
	This is an attempted lateral elbow view. The humerus is not at right angles to the beam resulting in a malpositioned lateral elbow view. The anterior and posterior fatpad signs are probably present but not well demonstrated on the malpositioned view. There is clear evidence of a type I radial head fracture.

This 17 year old girl presented to the Emergency Department after falling from a car bonnet . She had pain in her left elbow and a decreased range of movement. She was referred for elbow radiography.

	The AP elbow was performed using a cross-table technique. There is a suggestion of a lucent line in a vertical/oblique orientation through the radial head.
	The lateral elbow position is not a true lateral. Despite this limitation, there are clear anterior and posterior fatpad signs (arrowed).
	This is an attempted oblique elbow view. The elbow has been malpositioned in the collimated field resulting in non-demonstration of the medial elbow anatomy. The radial head has been successfully demonstrated and no displaced fracture is evident.
	This is a 30 degree tube angle radial head view demonstrating a Mason type I radial head fracture.

Comment

Subtle radial head fractures may only be demonstrated conclusively on the 45 degree radial head view image.

This 30 year old man presented to the Emergency Department after falling during a game of soccer . He had pain and swelling in his right elbow and a decreased range of movement. He was referred for elbow radiography.

	The AP elbow view image is unremarkable. (the elbow is slightly flexed in this view)
	The lateral elbow position is not a true lateral. Despite this limitation, there is a subtle cortical disruption of the radial head suggesting the possibility of a radial head fracture. In addition, an anterior fatpad sign is visible and possibly a very subtle posterior fatpad sign.
	This is a malpositioned lateral view image demonstrating a Mason type I radial head fracture.
	The oblique view of the radial elbow similarly demonstrates a subtle cortical defect in the radial head.

This 19 year old male presented to the Emergency Department after falling off his pushbike. He had pain and a decreased range of movement in his right elbow. He was unable to pronate and supinate his right hand. He was referred for elbow radiography.

	This is an AP elbow view image with the elbow in partial flexion with the patient's hand pronated (note the radius crossing the ulna). The positioning is biased to demonstrate the humerus. (see option 3 above) No displaced fracture is clearly demonstrated.
	This is also an AP elbow view image with the forearm in contact with the image receptor. Note that the radius crosses the ulna indicating that the wrist is probably pronated instead of supinated. No displaced fracture is clearly demonstrated.
	The lateral elbow view image demonstrates anterior and posterior fatpad signs (white arrows). The radial head appearance is suspicious of a radial head fracture (black arrow)
	This is a 30 degree radial head view image. There is a clearly demonstrated fracture of the radial head (Mason type II)

Comment

The improved demonstration of the radial head fracture on the dedicated radial head view illustrates the value of this projection

This 23 year old male presented to the Emergency Department after falling off his skateboard. He had an extremely swollen and painful left elbow. He was referred for elbow radiography.

	This is also an AP elbow view image with the elbow in partial flexion and the forearm in contact with the image receptor. There are several lucent lines through the radial head suggesting a comminuted fracture.
	This is an AP elbow view image with the elbow in partial flexion. The positioning is biased to demonstrate the humerus. (see option 3 above) There is a fracture of the radial head- possibly comminuted in a peace sign configuration (also called a Mercedes sign) http://eorif.com/Elbowforearm/Radial%20Head%20fx.html
	The lateral elbow view image demonstrates anterior and posterior fatpad signs- they are not sharply delineated but, nevertheless, are strongly suggested.
	This is a 30 degree radial head view image. No displaced fracture is convincingly demonstrated.
	This is a reverse oblique view image. A vertical fracture line through the radial head is demonstrated.

Comment

This case demonstrates the value of the AP elbow view with the patient's elbow in partial flexion and the humerus in contact with the image receptor. This view produces a partially axial projection of the radial head which demonstrated the nature of this fracture well.

This 16 year old girl presented to the Emergency Department after falling onto her left arm. She had a painful left elbow. She was referred for elbow radiography.

	This is a modified AP elbow position with the upper arm/humerus in contact with the IR and the elbow in partial flexion. There is a suggestion of a radial head cortical irregularity (arrowed).
	This is the matching AP view of the flexed elbow with the forearm in contact with the IR. Note that the radial head is demonstrated in true profile compared with the AP view image above. There is a cortical discontinuity of the radial head (arrowed).
	The lateral elbow view image clearly demonstrates an anterior fatpad sign (arrowed) with a less obvious posterior fat pad sign (unmarked).
	The lateral view was repeated which resulted in an improved demonstration of the posterior fatpad.
	In desperation to clearly demonstrate the suspected fracture of the radial head, the radiographer performed an AP view of the radial head with tube angulation toward the elbow. This is essentially the same as the initial AP elbow projection with tube angulation in lieu of elbow flexion. The radial head fracture is similarly demonstrated (white arrow).

Comment

This case demonstrates the subtlety of some radial head fractures. Undisplaced fractures of the radial head are sometimes impossible to demonstrate on first presentation and may not show until the second, or even third radiographic examination. Note also that subtle differences in the lateral elbow position can improve the demonstration of the elbow fat pads.

This 43 year old lady presented to the Emergency Department after falling onto an outstretched hand. She had a painful left elbow which she was unable to extend. She was referred for elbow radiography.

	The AP elbow view demonstrates partial elbow flexion. There are several indistinct lucent lines through the radial head suspicious of a fracture.
	There are indistinct, but nevertheless convincing, anterior and posterior fatpad signs (arrowed).
	The radial head view demonstrates a minimally displaced fracture of the radial head
	The oblique view of the elbow demonstrates the radial head fracture convincingly.

Comment

This case demonstrates the potential value of the external oblique view of the elbow in demonstrating radial head fractures.

This 15 year old male presented to the Emergency Department after falling onto his right arm. His elbow was examined and found to be swollen and there was a limited range of movement in the elbow joint. He was referred for right elbow radiography.

	The patient was unable/unwilling to extend his elbow. This AP elbow view image is taken with the upper arm in contact with the IR. This causes distortion of the bony forearm anatomy. There is a very subtle step/discontinuity of the radial head.
	This AP elbow view is taken with the forearm in contact with the IR. NOte that the radial head is almost perfectly profiled in this view (compare with the image above). Once again, there is a very subtle breach in the cortical margin of the radial head.
	The lateral elbow position is not a true lateral. There are anterior and posterior fat pad signs (arrowed). No facture is demonstrated.
	The radial head view demonstrates a subtle cortical irregularity (arrowed).
2 Week Follow-up Imaging	2 Week Follow-up Imaging The radial head fracture is more convincing on the two week follow-up images
2 Week Follow-up Imaging	2 Week Follow-up Imaging The radial head fracture is convincingly demonstrated on the follow-up radial head view
2 Week Follow-up Imaging	2 Week Follow-up Imaging A cortical step is seen in the contour of the radial head.

Comment

This case demonstrates a typical undisplaced radial head fracture. The follow-up imaging of the elbow clearly demonstrates the radial head fracture.

	This 9 year old girl presented to the Emergency Department after falling off a chair. On examination, she was found to have a painful left elbow. She was referred for left elbow radiography.
	The lateral elbow image demonstrates multiple soft tissue signs.
	There are anterior and posterior fatpad signs (white arrows). There is a raised supinator fatpad (black arrow)
	This is a radial head projection image. There is irregularity of the proximal radial metaphysis.
	The arrowed irregularity of the proximal radial metaphysis probably represents a Salter Harris II fracture.

Patients with radial head fractures will occasionally provide a challenge for the trauma radiographer. Achieving good quality imaging in a patient who is in considerable pain can test the innovative/adaptive skills of junior and seasoned radiographers alike. Radial head fractures can be subtle requiring a balanced consideration of the mechanism of injury and subtle soft tissue signs when deciding which patients to pursue with supplementary views and which to save from further irradiation. Some radial head fractures will only be demonstrated radiographically on second or even third presentations.