The Relationship Between Morphometric Measurements, Severity, and Success of Zygomatic Arch Fracture Reduction.

Purpose: Identify associations between preoperative radiographic measurements and clinical findings of zygomatic arch fractures and postoperative radiographic measurements. Based on those findings, propose a comprehensive treatment algorithm for the solitary zygomatic arch fracture and combined zygomatic arch-zygomatic complex fracture.

Methods: Retrospective cohort study with patients referred to our department for zygomatic arch fractures between 2013 and 2018. Data analyzed included patient demographics, clinical evaluation, and radiographic information. Predictor variables were preoperative morphometric measurements: the initial latero-lateral (LL) defect was determined by the difference between the preoperative LL distances of the fractured and the healthy arches, LL distance was measured from the midsagittal plane in the cranium to the inner cortex of the most displaced arch segment, initial arch coronoid distances were measured from the medial part of the most dislocated arch fragment to the lateral aspect of the coronoid, and the anterior-posterior telescoping was measured as the distance between the 2 points in the arch that lost continuity and overlapped as a result of the fracture. The outcome was defined as the residual defect. It was calculated as the ratio between the postoperative remaining LL distance and the initial LL defect.

Results: A total of 179 cases were enrolled, all involving head residual defects. Statistical analysis was performed only on 149 medially displaced fractures. Results show that an initial LL defect larger than 3.5 mm has an 86.3% chance of remaining with a better residual defect (<84.1%), P = .001. Cases with antero-posterior (AP) telescoping > 1.45 mm showed a 72.4% chance of remaining with a poor residual defect >84% (P = .003). Arch-coronoid initial distance showed little effect on the chance of remaining with a large remining defect (P = .417, CI = 95%) CONCLUSION: Based on our results, we found that morphometric measurements can be used to predict the reduction results and can assist the clinician in choosing the optimal reduction method and thus increasing the success rate.