Given the task definition and input, reply with output. Given an abstract, indicate which of the provided candidate titles (Option1 and Option2) best describes it (respond with the text of the title, not option1/2).

Abstract: In the case of a 19-year-old man, overuse of his nondominant forearm resulted in a radioulnar synostosis. Despite the persistence of the synostosis, the patient adapted to loss of forearm rotation. No further treatment was necessary. Isolated fractures of the ulnar shaft are slow in healing. Several authors observed that early function may be beneficial. However, excessive activity causing motion at the fracture site may cause subperiosteal hemorrhage and soft tissue trauma and may stimulate exuberant callus formation. Fractures of the ulnar shaft, even undisplaced, need to be immobilized to prevent overuse.
Which is the apt title for the abstract? option1: Radioulnar synostosis following an isolated fracture of the ulnar shaft. A case report. option2: Study of the protective effect of the primary hamster kidney cell rabies vaccine [letter]
Radioulnar synostosis following an isolated fracture of the ulnar shaft. A case report.