Quantitative assessment of symmetry recovery in navigation-assisted surgical reduction of zygomaticomaxillary complex fractures.

PURPOSE: To evaluate the effects of surgical navigation in zygomaticomaxillary complex (ZMC) fracture reduction. ZMC symmetry was assessed quantitatively. MATERIALS AND METHODS: The sample comprised 25 patients who underwent surgical reduction of comminuted ZMC fractures. They were divided into two groups according to the use of surgical navigation. Reduction outcomes were evaluated using three-dimensional computed tomography models. Five pairs of landmarks were identified on all craniofacial models, and asymmetry scores were calculated based on their coordinates. In quantitative analyses, symmetry and orbital volume were compared between groups. RESULTS: All patients recovered uneventfully. Greater symmetry was observed in the navigation group than in the control group for three of the five pairs of landmarks (p < 0.05). Although postoperative volumes of the injured orbits were similar between the two groups (p > 0.05), reduced orbital volumes were larger in the navigation group, indicating better restoration of the fractured orbits (p < 0.05). CONCLUSIONS: The use of surgical navigation can increase postoperative symmetry of the bilateral ZMC. The quantitative evaluation of clinical outcomes is precise and highly reliable.

Assessment of Infraorbital Hypesthesia Following Orbital Floor and Zygomaticomaxillary Complex Fractures Using a Novel Sensory Grading System.

PURPOSE: Introduction of a novel sensory grading system to assess the incidence and long-term recovery of infraorbital hypesthesia following orbital floor and inferior orbital rim fractures. METHODS: Patients who presented for evaluation of orbital floor and/or zygomaticomaxillary complex (ZMC) fractures between January 2015 and April 2016 were analyzed. Two-point subjective infraorbital sensory grading in 5 discrete anatomic areas was performed. Fractures were repaired based on traditional criteria; hypesthesia was not an indication for surgery. The sensory grading system was repeated a mean 21.7 months (range 18-28) after initial fracture. RESULTS: Sixty-two patients (mean 41.8 years) participated in the initial symptom grading, and 42 patients (67.7%) completed the 2-year follow-up. Overall, 20 of 42 patients (47.6%) had some infraorbital hypesthesia. There were fewer with isolated orbital floor fractures versus ZMC fractures (31.8% vs. 68.4%; p = 0.019). Two years postinjury, 9.1% and 40.0% with isolated floor and ZMC fractures, respectively, had persistent sensory disturbance (p = 0.0188). Of patients with sensory disturbance on presentation, 71.4% with isolated floor fractures and 38.5% with ZMC fractures experienced complete sensory recovery (p = 0.1596). Patients with isolated floor fractures had improved recovery after surgery (100% vs. 33.3% recovery; p = 0.0410). Patients with ZMC fractures showed no difference in sensory prognosis between those repaired and observed. CONCLUSIONS: In this pilot study, isolated orbital floor fractures carried a good infraorbital sensory prognosis, further improved by surgical repair. Zygomaticomaxillary complex fractures portended a worse long-term sensory outcome, unaffected by management strategy. This study validates the novel sensory grading system in post-fracture analysis.