Infraorbital nerve recovery after minimally dislocated facial fractures

Abstract

There is evidence that rigid fixation of zygomaticomaxillary suture enhances the recovery of the infraorbital nerve compared with other means of surgical treatments. There is, however, no agreement as to whether any surgery decreases the number of sensory disturbance in cases with little or no dislocation, or whether infraorbital numbness alone should be considered an indication for surgery. An operation may even increase the edema and hemorrhage around the nerve. This retrospective study was carried out among patients with infraorbital hypesthesia but little or not at all dislocated midfacial fractures. Two special types of trauma patients were selected; those with a blow-out fracture but an intact infraorbital rim (BO) and those with a zygomaticomaxillary complex fracture (ZMC). A questionnaire was sent to the patients (n = 226) 2.2 years (mean) after the accident. There were 128 responses (BO n = 41, ZMC n = 87). Of these, 27 BO and 29 ZMC patients had been treated by observation. An orbital exploration had been carried out in 14 BO patients, and 58 ZMC patients had received malar bone elevation without rigid fixation. At the end of the follow-up period nontreated patients had fewer symptoms than those who had had surgery. This was clearer in the ZCM group (symptom free 69% vs. 52%) than in the BO group (69% vs. 50%). The differences between surgically and nontreated BO or ZMC patients, however, were statistically nonsignificant. According to our findings, exploration of the orbital floor or an attempted elevation of a minimally or nondislocated fracture of the ZMC does not enhance the recovery of the infraorbital nerve. On the contrary, the procedure may itself increase the morbidity and sensory dysfunction. Further studies are needed to determine whether the results could be improved by selective decompression of the infraorbital nerve and a rigid fixation.