Traumatic Thumb Radial Sagittal Band Injury Mimicking EPL Rupture.

We present the case of a closed traumatic disruption of the thumb radial sagittal band (RSB) that sonographically mimicked rupture of the extensor pollicis longus (EPL) tendon. This injury was treated with primary repair of the RSB and lead to a good functional outcome for the patient. This case report highlights how early recognition and treatment can lead to a good functional outcome.