Symptoms, diagnosis, therapy and clinical outcome of 2 horses which acquired a complete rupture of the extensor carpi radialis tendon by accident are described. The resulting gait abnormalities are very typical, so that the problem can be diagnosed already by clinical examination. With the help of ultrasound the diagnosis could be confirmed and the degree of damage quantified. The open wounds in the carpal region were surgically treated in a standing position and the limbs of both horses were kept under a splint bandage for 6 to 8 weeks. Prognosis in these cases was good, as both horses returned within 6 months back to their previous work.