Recovery of the Infraorbital Nerve Following Open Reduction and Fixation Surgery of Zygomaticomaxillary Complex Fractures-A Prospective Cohort Study Based on Quantitative Sensory Testing

This study aimed to assess the sensory function of the infraorbital nerve in patients with fractures of the zygomatic complex who underwent open reduction and internal fixation at different time points using quantitative sensory testing, which was established by the German Neuropathic Pain Research Network, comprising a 7-item mechanical and thermal sensory test. A total of 21 patients (age range 17-46 y, 14 males) with unilateral zygomatic complex fractures were included. Quantitative sensory testing was conducted before the operation and at 1 week, 3 months, and 6 months operatively, with cold detection threshold, warmth detection threshold, cold pain threshold, heat pain threshold, mechanical detection threshold, mechanical pain threshold, pressure pain threshold, and vibration detection threshold being measured in bilateral infraorbital regions. Notable changes in sensitivity were observed in all values except for the mechanical pain threshold. In the majority of patients with zygomaticomaxillary complex fractures, infraorbital hypoesthesia was significantly improved within 3 months postoperatively, and almost complete recovery could be achieved by 6 months postoperatively.