Symposium on maxillo-facial trauma. 3. Pitfalls in the management of zygomatic fractures.

Abstract

AbstractRecognition of various types of zygomatic fractures and their postreduction stability is essential for correct diagnosis and proper treatment of zygomatic fractures.It should be fully recognized that the zygoma, upon dislocation, may rotate around a vertical or longitudinal axis, and may be displaced medially, laterally, posteriorly or inferiorly, and that postreduction stability differs considerably depending upon the direction of rotation or displacement of the fractured zygoma.Diagnosis of the type of zygomatic fracture can be made on the three X‐ray views: Waters, submentovertical and Caldwell. The Waters view is the best single view for evaluation of zygomatic fractures. It should be noted, however, that posterior displacement of the zygoma may not be well shown in this view, because the zygoma is often displaced along the course of the X‐ray beam. The submentovertical view is indispensable for zygomatic arch fracture (Type II), posterior displacement (Type Vc), and medial and lateral rotation of the zygoma around the vertical axis (Type III, a and b). The Caldwell view is an important view for Type IV fractures which rotate around the longitudinal axis, and Type V fractures with medial (Va), lateral (Vb), and inferior (Vd) displacement. Diagnosis of zygomatic fractures should not depend upon the Waters view alone.Classical Temporal Approach. This approach is simple and most effective for depressed arch fractures but not effective for displacement or rotation of the zygomatic body. Elevation of the zygoma via this route may be hazardous for medial displacement (Type Va) and medial rotation around the vertical axis (Type IIIa). Transbuccal elevation is recommended as the standard initial method for all types of zygomatic fractures except for arch and rim fractures. This approach is particularly effective for posterior displacement (Type VC) and lateral rotation around the vertical axis (Type IIIb). Direct transorbital elevation via infraorbital and zygomatico‐frontal incisions should be used when the zygoma is impacted and cannot be reduced or when the fractured zygoma is unstable after reduction. This approach should also be used when there is a suspected blow‐out fracture of the orbit. This approach is particularly useful for fractures rotated around the vertical or longitudinal axis (Type III and IV) as well as for inferior displacement of the zygoma (Type Vd). Supraorbital elevation via an eyebrow incision is an effective method for posterior displacement Type Vc), but not for lateral or inferior displacement (Type Vb and Vd) or fractures rotated around the longitudinal axis of the zygoma (Type IV). Direct interosseous wiring is the most dependable and effective method of fixation of the zygoma.As a guide to treatment of zygomatic fractures, the Rowe and Killey classification is superior to the widely accepted Knight and North classification. The author proposes a modified Rowe and Killey classification which will more readily help to predict the postreduction stability and thus help to select the method of treatment according to the type of fracture.