Navigation-Guided Management of Comminuted Zygomaticomaxillary Complex Fracture Concurrent With Orbital Reconstruction.

Background: Comminuted zygomaticomaxillary complex (ZMC-C) fracture with orbital reconstruction poses challenges for surgeons. Navigation-guided technique may be valuable for surgical reduction.

Purpose: This study aimed to measure the difference error between planned and actual reduction of ZMC-C fracture with orbital reconstruction using navigation-guided technique.

Study design, setting, sample: This retrospective single-arm cohort study involved subjects with ZMC-C and orbital fractures from Jan 2017 to Jun 2019 at the Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China. Subjects with brain damage, unstable vital signs, allergy to titanium alloy implants, trauma to other facial bones or postoperative facial trauma were excluded.

Main outcome variables: The primary outcome variable was the mean 3-dimensional (3D) (Euclidean) distance error between surgical plan and actual outcome. Secondary outcomes included mean absolute distance error in transverse, vertical and anterior-posterior planes, visual analog scale score of subjects' self-satisfaction with facial aesthetics and function, orbital volume, exophthalmometry, position of bilateral zygomatic bones and surgical complications.

Covariates: Covariates included age and sex.

Analyses: Outcomes were tested using t-tests with significance at P < .05 to determine differences between preoperative and postoperative measurements and symmetry.

Results: The sample included 20 subjects with a median age of 39 years (interquartile range = 24.5) and 19 (95%) were male. The mean 3D distance errors were 0.5 ± 0.3 mm at the midpoint of the fracture line at the zygomatic frontal suture, 0.7 ± 0.3 mm at the most prominent point on the surface of zygoma and 0.6 ± 0.4 mm at the intersection point of the zygomatic alveolar buttress and fracture line. The maximum mean absolute distance error was 0.8 ± 0.2 mm. Postoperative visual analog scale score improved in all subjects. Mean orbital volume was reduced by 2.2 ± 0.6 cm³, and enophthalmos improved to 0.4 ± 0.3 mm (all P < .01). There were no significant differences in exophthalmometry, orbital volume and position of bilateral zygomatic bones between the affected and unaffected sides (P > .05).

Conclusion and relevance: Deficient movement in the anterior-posterior plane mainly contributes to 3D distance error. The mean distance error was clinically acceptable with the aid of navigation-guided technique in managing ZMC-C fracture with orbital reconstruction.