Is Zygomatic Osteotomy a Viable Option to Achieve Symmetry and Stability in Post-traumatic Residual Deformity of the Zygomaticomaxillary Complex?

Abstract

Purpose: In residual deformity cases, it is difficult to reposition the zygomaticomaxillary-complex (ZMC) intraoperatively, due to resorbed fracture edges, and lack of zygoma analysis to 3-dimensionally quantify the deformity. Instability after zygomatic osteotomy and miniplate fixation (ZOMF) due to the gap between osteotomized segments, scar tissue, muscle pull, and other factors is also unknown. The study aims to evaluate symmetry and stability after ZOMF.

Materials and methods: In this prospective study, a ZMC analysis was designed and patients with unilateral post-traumatic residual deformity (>10 weeks) of ZMC were treated with ZOMF. Measurements were evaluated on affected and unaffected sides at preoperatively, immediately, and 6 months postoperatively using MIMICS software. The primary outcome variable was the symmetry and stability of ZMC. Secondary parameters were changes in orbital volume, diplopia, ocular motility, mouth opening, and patient satisfaction. P < .05 was considered statistically significant. The continuous variables were compared by paired t-test. The change within the continuous variable with time was assessed by repeated measure ANOVA, followed by multiple comparisons using the Bonferroni test. The changes within the categorical variable were assessed by the McNemar test.

Results: Ten patients were enrolled (mean age = 29.2 ± 9.97 years; male:female = 9:1; right:left = 4:6). The mean duration from trauma to surgery was 34.84 ± 31.35 weeks. There was an improvement in the symmetry in anteroposteriorly (P = .005), mediolaterally (P = .001), and at the arch (P = .011) postoperatively. All parameters remained stable at 6 months postoperatively (difference not significant, P > .05); with the median satisfaction score of 4 of 5. Significant improvement in mouth opening (P = .014) and orbital volume (P = .001) was noted.

Conclusions: Virtual measurements as per the proposed protocol helped in communication and quantifying ZMC. Four-point fixation with miniplates provided enough stability over the 6-month follow-up period.