Differential sonographic features of the extensor pollicis longus tendon rupture and other finger tendons rupture in the setting of hand and wrist trauma

PURPOSE: To investigate the difference between sonographic findings in extensor pollicis longus tendons rupture and other finger tendons rupture in patients sustaining hand and wrist trauma. METHODS: Twenty-four patients who presented with signs and symptoms clinically suspicious for tendon injury and surgically confirmed tendon rupture were included in this study. We analyzed 6 sonographic features: discontinuity of the tendon, pseudomass formation, decreased echogenicity of the tendon, retraction of the ruptured tendon, fluid collection within the tendon sheath, and the motion of the tendon. We compared the sonographic features of ruptured extensor pollicis longus tendons with the other ruptured finger tendons. RESULTS: Discontinuity of the tendon was the most common sonographic findings and retraction of the ruptured tendon was the second most common findings. Fourteen of 16 cases with a dynamic study on sonography showed loss of normal motion of the tendon. Pseudomass formation was the second most common feature in ruptured extensor pollicis longus tendons, in contrast to the other ruptured finger tendons (p < 0.05). CONCLUSION: Using ultrasonography, detection of discontinuity of the tendon, retraction of the ruptured tendon, and limitation of tendon motion could be very helpful for diagnosing a tendon rupture in hand and wrist trauma. Pseudomass formation could be more specific for diagnosing extensor pollicis longus tendon ruptures compared with other finger tendons.