We report a rare case of a da Vinci robotic arm failure during a laparoscopic robot-assisted radical prostatectomy. The articulation joint of an Endowrist needle driver was broken and positioned at such an angle that made it impossible to remove through the trocar. In addition, it was later discovered that a small piece of the instrument was detached and remained inside the abdomen of the patient without even having been identified on subsequent radiological evaluation. In order to remove the broken instrument, we had to uninstall it from the robot arm and a bigger incision had to be made in the abdominal wall of the patient. The operation was completed without any other incidents. Testing the broken instrument for integrity is recommended to avoid this rare complication.