Variability in Syndesmotic Screw Angles During Ankle Fracture Fixation: Insights From Postoperative CT Analysis

Area of Science:

• Orthopedic Surgery
• Radiology
• Biomechanics

Background:

• Syndesmotic screw fixation is standard for ankle fractures with syndesmotic disruption.
• Current guidelines suggest screw angles of 30°-45° relative to the anterior foot.
• Evidence for routine achievement and necessity of these angles is limited.

Purpose of the Study:

• To evaluate actual screw angles used in clinical practice for syndesmotic screw fixation.
• To identify radiographic factors influencing successful syndesmotic reduction.
• To compare achieved angles with recommended surgical guidelines.

Main Methods:

• Retrospective analysis of 100 patients with ankle fractures treated with syndesmotic screw fixation.
• Postoperative CT scans assessed screw angle, tibiofibular distances, and reduction quality.
• Statistical analysis identified associations between screw trajectory and reduction parameters.

Main Results:

• 72% of patients achieved good syndesmotic reduction.
• Posterior screw placement and steeper screw angles were associated with poor reduction (p=0.013).
• Poor reductions showed increased tibiofibular distances and diastasis (p<0.001).

Conclusions:

• A significant gap exists between recommended and actual screw angles in practice.
• Lower screw angles (~15°) correlated with better syndesmotic reduction.
• Findings challenge the strict adherence to 30°-45° guidelines, suggesting further research for refined recommendations.