This IOW comes from Dr. Karen Bowers and MS-4 Thatcher Heumann, who used the ultrasound to evaluate a patient in the MTC who presented with continued pain and swelling at the site of a previous GSW sustained approximately one month prior to presentation. The patient was splinted on his initial presentation one month ago, at which time he was diagnosed with a minimally displaced ulnar fracture; however, he had removed the splint and fell onto his outstretched arm with an increase in pain, at which time he returned to the ED.
Using the linear probe, the team was able to assess the radius and ulna at the site of the injury and obtained the images below.
Can you make the diagnosis?
The images obtained showed an irregularity of the cortex of the ulna demonstrated as a discontinuity of the normally hyperechoic bony structures. The above imaging also shows additional hyperechoic structures in close proximity to the fracture site.
Though the patient had a previous GSW, the hyperechoic structures in proximity to the fracture site did not have the significant amount of posterior shadowing that would be expected of a metallic foreign body such as a retained missile. The hyperechoic structures noted above are more consistent with callous formation with calcifications around the fracture site consistent with normal wound healing.
Given the callous formation and minimally displaced nature of the fracture noted above, there was less concern for acute fracture in the setting of the patient’s fall the day of presentation; however, determination of re-injury in the setting of previous trauma can be difficult using ultrasound given that callous formation can obscure evidence of new trauma when evaluated using ultrasound. Plain radiography confirmed that there was no new fracture and the patient was re-splinted and discharged with follow up to orthopedic surgery.