Assessment of the adequacy of closed reduction in fractures of the zygomatic arch using "C"-arm image intensifier.

Major problems in closed reduction of isolated, minimally displaced, and depressed zygomatic arch fractures are blind nature of the technique, reliability on digital palpation, reduction click, and step deformity between fragments. The purpose of this study was to objectively confirm the adequacy of closed reduction intraoperatively and the usefulness of the "C"-arm image intensifier. A total of 12 patients with 1- to 8-day-old unilateral isolated and depressed zygomatic arch fracture underwent closed reduction under "C"-arm image intensifier. Of these patients, 9 were men and 3 were women, with age ranging from 18 to 32 years. Intraoperative prereduction and postreduction images were obtained using the "C"-arm image intensifier. Criteria for adequate reduction were the following: intrafragmentary gap less than 0.5 mm, no overriding of fragments, no depression of fragments, and no step deformity. After being clinically satisfied about the reduction, images on "C"-arm showed no intrafragmentary gap. In 3 patients, there were residual overriding and minimal rotation around the anteroposterior axis of the posterior fragment. In 1 patient, rotation and step deformity remained. In this patient, additional stabilization was provided. The "C"-arm image intensifier shows some poorly reduced or unstable isolated depressed zygomatic arch fractures that remain unidentified even after careful palpation. Thus, it plays a recognizable role to avoid the trouble of second intervention.