Objective: The purpose of this study was to examine the anatomic features and imaging appearance of the intersection of the extensor pollicis longus (EPL) tendon with the extensor carpi radialis brevis (ECRB) and longus (ECRL) tendons in cadavers and patients.
Materials And Methods: MR and CT tenography were performed on 10 cadaveric wrists, and tenosynovial endoscopy and dissection of the EPL tendon sheath were performed on five additional cadaveric wrists. A computer-assisted search of dictated MRI reports identified 12 wrists of patients with simultaneous EPL tenosynovitis and ECRB and ECRL tenosynovitis.