about ultrasound findings of post-traumatic ulnar nerve subluxation

This is the case of a direct blow to a flexed elbow. The X-ray and Mri exams show a condylar fracture of the humerus, with a partial cortical bone detachment; a gross joint capsule distension is also evident.

Coronal Xbone-T1w Mri scan (0.3 Tesla) and Plain Radiography.

Coronal Stir (left) and T1w (right) Mri scans of the same patient (0.3 Tesla).

Why ultrasound in this case? Because after 1 month the patient feels pain on the posterior-medial aspect of the elbow, especially during the flexion-extension active movement, with distal pain irradiation to the forearm.

The dynamic ultrasound exam better depicts the clinical picture of a post-traumatic ulnar nerve subluxation at the sulcus ulnaris, togheter with a gross joint synovitis.

Axial T2w (left) and Stir (right) Mri scans of the same patient (0.3 Tesla).